Scuba Slang and Technical Terms

By Members of SCUBA-L,
including Wrolf Courtney and Jan Faust
Click here for some great books about diving.
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z





50/50Nitrox50. 50% O2, 50% N2. Commonly used as a travel mix.
80/20Nitrox80. 80% O2, 20% N2. See stroke mix.

A
AASAlternate Air Source, such as a pony bottle.
ab(s) (1)Abalone(s), a California shell fish pursued by divers and sea otters. The sea otters are better at it.
abs (2)What studly macho divers think they have but don’t.
ab ironsTool used to get abalone off rock.
ABLJAdjustable Buoyacy Life Jacket, horse-collar style, forerunner of the BC. (British)
AGAA popular full face mask, the AGA Divator MKII. In New York pronounced “auger” (with a strong “AW” sound in the beginning).
AGA and com gearAn AGA equipped with a microphone and speakers to allow a diver to communicate by voice, typically through a wire to a surface support team.
AGEArterial Gas Embolism, bubble causing obstruction to a blood vessel
AIAssistant Instructor
air hogDiver who sucks tank dry in record time. (Or in less time than it takes their buddy.)
aluminum 80Most common tank in industry. Nominal capacity 80 cu. ft.
alpha flagAlpha Flag. Diver Down, Keep Clear! International maritime signal flag< meaning "Diver down, keep clear!". Compare with the U.S. dive flag
AOWAdvanced Open Water (PADI qualification)
artificial spitSmall bottles of liquid purchased at exorbitant prices by divers who do not
know better to keep their masks defogged. Made by having divemaster candidates
fill small bottles with REAL spit.
artifactAn item removed from a wreck. See souvenir.
ASDAtrial Septal Defect, ‘Hole in Heart’
ATAAbsolute pressure. Includes the atmospheres of pressure you rack up under the water and the atmosphere of pressure at the sea level ATM machine.
AVArtificial Ventilation. EAR. (British)

B
back rollLeave a boat by sitting on its rail and then rolling backwards into the water.
backscatterWhat you get in your picture after bozo the CN kicks the bottom.
bail-out bottle (1)A small bottle filled with your favorite beverage to hold you until your friends come to bail you out of the Cozumel jail.
bail-out bottle (2)SD
bail-out bottle (3)Extra cylinder of gas carried by a surface supplied diver or a rebreather diver to enable them to reach safety in the event of an interruption of their primary supply. For saturation divers, this would typically be to reach a habitat.
barotrauma Damage caused by water or air pressure.
BCBuoyancy Compensator.
Braille diveViz so bad you have to just feel your way around.
BCDBuoyancy Control Device.
beaverOn old wetsuit jackets it hung down in the back. You pulled it through your legs, and velcroed it to the front of the jacket. Also called a beaver tail.

Historical note: Some ‘real men’ claim to have been able to fasten this without obtaining a high pitched voice. This is probably apocryphal.
bend-O-maticDive computer
bent (1)Suffering from DCS.
bent (2)Suffering from too much tequila.
blowing offOmitting something, typically omitting required decompression.
blue waterUn-green water. Typically found somewhere you are not. Like Cozumel.
bolt snapBrass or stainless steel fitting with a gate activated by your thumb.
bondage wings (1)Impressive looking back mounted BC by OMS. Features dozens of little rubber straps to confine the bladder when not inflated. Implicated in a number of tech diving tragedies.
bondage wing (2)A diving S&M toy
BottleCylinder.
bottom dumpValve on the bottom of a BC which allows you to empty air while in a head-down mode.
bottom mix (1)
Mix breathed at the bottom, especially when other gas mixes are used for travel and/or deco. Bottom mix should have ppO2 less than 1.4. END is typically chosen to be 99 fsw or 132 fsw.
bottom mix (2)What is found in the bottom of used margarita glasses.
bounce
or bounce dive
To dive and surface at intervals repeatedly. A dive where you turn around to ascend immediately after reaching the bottom.
BSACBritish Sub Aqua Club.
BTBottom Time – definition is agency dependant.
buddy (1)For the benefit of officious Divemasters – your nominal partner when you practice the “Same Day, Same Ocean” diving principle
buddy (2)The person who always sees more interesting things on a dive than you do; knows the scientific names of all of those furry little green things that live under rock ledges; reveals to the rest of the passengers that your diving techniques are all wrong; and leaves you to wash out their gear at the end of the day.
buddy (3)A person you’re happy to go for a drink with.
bugLobster. Also crawfish in Louisiana
bug bagLobster Bag. Generally of mesh and/or canvas. To carry all the lobsters that you catch, or the artifacts you recover.
bug huntingHunting for bugs.
butt-mountingDangling the battery pack of a cannister light underneath your doubles, rather than on the right hip. Considered the height of strokery by Hogarthians.
BWRAFPADI training acronym: “Begin With Review And Friend”. Alt: “Bad Women Really Are Fun”; “Big White Rabbits Are Furry”; “Boogie With the Rich And Famous”; “Bruce Willis Ruins All Films”.

C
canister lightA light where the battery is strapped to your belt and the light is held in your hand.
CAPSCave mapping software and electronic survey equipment
cattle boatWe’ve all been there, done that. There are no cows on a cattleboat, at least not the four legged kind.
CESAControlled Emergency Swimming Ascent
C-cardCertification card
chamber (1)Hyperbaric chamber, for diagnosis and treatment of DCS
chamber (2)The room that contains the pot.
chamber ride (1)To be compressed in a chamber.
chamber ride (2)What you do on your last day at the hotel in Cozumel. See chamber (2).
charlie foxtrotEuphemism for clusterfuck, derived from initials.
check-outWhat you do on your last day at the hotel in Cozumel.
chokesForm of DCS in which you are unable to breathe effectively. Generally fatal unless treated quickly with on-site O2 and prompt recompression.
chummingFeeding the fishes. Performed voluntarily by fishermen
in order to attract large fishes. Performed by divers involuntarily.
clear (1)equalize ears
clear (2)free of nitrogen – clear to fly
clusterfuckComplete pandemonium, often the result of strokery.
Diving on the wrong day with the wrong equipment and the wrong attitude.
American. See incident pit.
CMCutis marmorata.
CMASConféderation Mondiale des Activitiés Subaquatiques, or in English the World Underwater Federation. International federation of scuba organisations. in the United States only the YMCA and the United Stateds Underwater Federation are members.
CNClueless Newbie.
CNS O2 toxicityAlso known as the Paul Bert Effect, tox, or oxtox.
computerDive computer. I can’t think of any time anyone thought we were talking about something with a keyboard.
CPRCardio-Pulmonary Rescusitation
cricketA lobster below the legal size.
cu. ft.Cubic feet. 1 cubic foot = 28.31685 liters.
cylinderTank

D
DANDivers Alert Network. When you have a big problem, call (919) 684-8111. Web site: http://www.diversalertnetwork.org.
DCIDecompression Illness, including DCS and AGE
DCSDecompression Sickness, the ‘bends’
DDRCDiving Diseases Research Centre, in Plymouth, England. The leading hyperbaric treatment and research centre in Britain.
dead reckoning (1)Navigating without using external referents, using compass, initial known position, and estimates of speed, current, wind, etc.
dead reckoning (2)The navigation method preferred by divers who never learned to use a compass. So called because they are frequently found dead.
deco mix (1)Gas mixture used for decompression, such as 80/20 or 100% O2.
deco mix (2)alt: 1 part Bacardis, 1 part Jack Daniel’s, 2 parts lemonade.
deep airLike deep throat, only different.
deep air divingalt: See muff diving
de-fizzingoff-gassing. See Wrolf’s Bubble Theory

alt: taking away feeshes fizzies
deserved hitDCS occuring after violating table or computer limits.
Doing It RightDIR
DIADoom Induced Nausea. Feeling in the pit of your stomach when you are about to do a dive
which is completely out of your comfort zone or experience. A George-ism.
DIN valves (1)Superior alternative to a yoke fitting for first stage. Screws in rather than clamps on, and O-ring is “captured” inside valve, reducing chance of O-ring failure.
DIN valves (2)The noise made when insufficient care is taken loading tanks into a vehicle, and the valves are banging together.
DIRTerm invented by George Irvine III to describe the practices that he and others
derived from Hogarthian principles.
See Hogarthian Diving Style
diveDoes anyone think this involves a springboard?
dive babeWoman who is a real diver – opposite of a chick
dive chickFemale diver who puts on make-up; brushes hair; has her boyfriend assemble her kit; and then has him carry it to the water before doing her dive.
dive dryDiving in a dry suit.
dive flagRed flag with white diagonal stripe from top of staff to bottom of fly: U.S. Dive Flag. Means the same as the international alpha flag, but is almost unknown outside the U.S. and cultural vassals. Within or near U.S. waters, the best policy is to fly both. Outside, fly the alpha flag.
DMDive Master
double-diskingUsing 2 burst disks on the valve of your tank to decrease the chance of losing all your air.
double steel 104’sPair of steel cylinders, nominal capacity 104 cu. ft, connected together with bands and a manifold.
DPVDiver Propulsion Vehicle. Scooter.
drift decohanging from a lift bag or DSMB during your deco (usually for high currents)
D ringsD-shaped rings. Attach to BC webbing with weight retainers.
DSMBDelayed Surface Marker Buoy, SMB which is inflated at end of dive. (British)
DVDemand Valve, usually the second stage. (British)

E
EADEquivalent Air Depth The depth at which air would cause as much decompression
obligation as a nitrox with a given fO2 at a given depth.
EAD = (Depth+33′) fN2/0.79 – 33′
= (Depth+33′) (1-fO2)/0.79 – 33′

All depths in fsw.
EAN, EANxEnriched Air Nitrox
EARExpired Air Rescusitation (preferred term now is AV in Britain)
EAVExpired Air Ventilation (British)
ENDEquivalent Narcotic Depth. The depth at which air would cause as much narcosis as a given mix and depth.
END is typically chosen to be 99 fsw or 132 fsw for a bottom mix.
Assuming that O2 and N2 are equally narcotic in practice; ignoring the narcotic potential of He (which is small, or perhaps non existent); and with depths in fsw:


END = ((1-fHe) (Depth / 33 +1)-1) * 33
= (Depth+33′) (1-fHe) – 33′

Many texts have not been updated to reflect the finding that O2 and N2 are approximately equally narcotic, and instead attribute all narcosis to ppN2. This
changes the formula to:
END = (( fN2/.791 ) (depth / 33 +1)-1) * 33 Obsolete
To make things worse, O2 & N2 are probably not equipotent for narcosis at all concentrations. It seems that at certain ratios, the O2 component is more narcotic than N2; and in other ratios, the N2 is more potent. See Narcosis on Wrolf’s Wreck for further details.
But assuming O2 & N2 are equipotent for narcosis is the best current practice.
EX-buddyperson who – after you have put up with all of their foibles – gets to the bar and insists that it’s your shout!

F
FAQCollection of Frequently Asked Questions (and answers).
fart bagDrysuit.
feed the fishvomit
FFAFeet First Ascent. Learning technique used by new drysuit divers.
FFMFull Face Mask
FFWFeet of Fresh Water
fin ladderA pole with pegs attached to either side to facilitate climbing out of the water with your fins on.
flounder gigA speargun spear with a SS cable attached to a T. This is used for flounder collecting.
fHe.
Fraction of helium (He) in a mix. In air, fHe = 0, unless you are near certain natural gas wells, a birthday party, or tech divers.
fN2.
Fraction of nitrogent (N2) in a mix. In air, fN2 = 0.791 = 79.1%. Actually this is a lie, counting the approximately 1% of other gasses in air (noble gasses etc.) as though they are nitrogen, but it is close enough.
fO2.
Fraction of O2 in a mix. In air, fO2 = 0.209 = 20.9%.
free diverBreath hold diver. Good guys, see Freediver brings gas
foul the hookTo tie the wreckhook upside down to facilitate leaving the wreck. Usually done by the last person up.
FSWFeet of Salt Water

G
gaitersRig designed to reduce the amount of air the lower legs of a drysuit. See FFA.
gerry lineGranny line.
get wetWhat all divers want to do – go diving.
golden triangleArea between the chin and the nipples where it is easiest to access equipment such as knives and regulators.
Goodman handleA U-shaped attachment to the light head of a canister light for attaching the light head to your hand.
GPSGlobal Positioning System
granny lineLine which goes from the stern platform or hangbar to the anchor line.

H
h valvetank valve with two outlets.
haloclineBoundary between layers of water of different salinities. Looks like a barrier of mist.
hangTo perform a decompression stop.
hang barBar slung underneath boat for convenience during decompression stops
hang lineHorizontal line rigged for convenience during decompression stops
hang tankExtra tank, ideally of deco mix, staged at deco stop.
Hawaiian slingA long spear with an elastic loop at one end and 3-pointed gig on the other. You catch the loop in your thumb and pull the spear back. When you let go, the spear shoots forward, hopefully into a fish.
helioxBreathing mix of helium and oxygen.
hitIncident of DCS.
Hogarthian principlesPrinciples behind Hogarthian system, named for William Hogarth Main.
Originated for cave diving but now adopted more widely.
See Hogarthian Diving Style
Hogarth rigHogarth rigged dive gear.
Hogarth riggedA method of rigging your gear for maximum survivabililty.
homebrewmix, especially nitrox, brewed up at home, or by adding oxygen to a cylinder and then taking it to dive store for fill. Implicated in a number of fatalities.
hookahregulator for breathing surface supplied air, either from a tank or a compressor, typically down to about 30 feet.
hooverair hog
horsecollarthe old style floatation device (now BC).
HP hoseHigh Pressure Hose. Goes from 1st stage to air pressure gauge.
hydroHydrostatic testing for tank integrity

I
IANTDInternational Association of Nitrox and Technical Divers
inflatableGenerally means a RIB.
incident pitSeries of events which individually would not be dangerous, but each causes a problem,
which is increased by the next, until you have a major incident.
The incident pit is a conceptual ‘pit’ with progressively steeper sides.
Anything going wrong pushes you slightly further into the pit.
As the sides steepen, it gets progressively more difficult to get out.
British. See clusterfuck.
ingassingTaking on additional nitrogen (and/or other inert gases).
instroketorInstructor who perpetuates strokery by instilling in students his own defective attitudes and techniques.
IPIntermediate Pressure, i.e. the pressure between the first and second stages
isolating manifoldmanifold that also has a valve to isolate the two tanks, to preserve half the gas supply in the event of a failure.

J
Jersey reelA large spool designed to hold ¼ diameter sisal line. Used in conjuction with a lift bag.
Jon line6-8 ft. line used to attach diver to anchor/shot line for deco so you donšt wear your arms out. Named for Jon Hulbert, a well-known NE wreck diver.
J-valve
Old fashioned tank valve with a reserve lever, which signals that pressure is down to 300-500 psi by making breathing difficult. Often seen with reserve feature disabled on old steel 72s.

K
K-valveRegular tank valve
kelp crawlStrange motion used to get over kelp on the surface.
kit(Dive) Gear. British.

L
legal bugs Vs. shorts. Lobsters that are long enough to be taken, and do not have eggs on them.
lift bagA device which you attach to an object you would like to lift off the bottom. Shaped like a upsidedown garbage bag, you pump air into to raise your object.
loot and scootWreck diving in the Great Lakes.
LORANLong-range Navigation.


An obsolete radio navigation system using land-based radio transmitters before GPS.

Lorraine Smith Effectpulmonary O2 toxicity
LP hoseLow Pressure hose. Goes from 1st stage to 2nd stage or to inflator.

M
manifoldplumbing to connect to tanks so that one regulator can access the gas in both. See isolating manifold
MARESDiving equipment manufacturer.
mix [noun]mixture of gases, often a trimix
MODMaximum Operating Depth for a mix, given a maximum ppO2.
MOD = (max ppO2 / fO2 – 1) * 33 fsw

N
NACDNational Association for Cave Diving
NAUINational Association of Underwater Instructors.

Not Another Underwater Idiot.

Need Another Underwater Instructor.
NDLNo-Decompression Limit
NDSNo Decompression Stop – no decompression limit according to table or computer
newbieSome one new at diving, computers or anything else.
nitroxAny mixture of nitrogen and oxygen. Nitrox 32, Nitrox 36, Nitrox 50, Nitrox 80, etc:
Nitrox with 32%, 36%, 50%, and 80% of oxygen respectively.
Nitrox INitrox 32. The NOAA term, the term Nitrox 32 is more precise and therefore preferred.
Nitrox IINitrox 36.
NSS-CDSNational Speleological Society-Cave Diving Section

O
O2 cleanClean enough of combustibles such as oil to allow use with high pressure
O2.
ockyOctopus (British)
OCNObnoxious Clueless Newbie.
octoOctopus
OctopusExtra second stage regulator, for benefit of your buddy should they want to use your air.
offgassingReducing the load of nitrogen (and/or other inert gases).
OMSOcean Management Systems, an equipment vendor well known for their low pressure steel tanks, and also unfortunately for their bondage wings.
OOAOut Of Air
OSO.S. Systems, Inc., Shell dry suit manufacturer.
outgassingOffgassing
OWOpen Water. The lowest level of PADI certification for scuba diving.

P
PPressure
PADIProfessional Association of Dive Instructors.

Put Another Dollar In.

Pay And Dive Immediately.

Patches Available During Instruction.

Produce Another Dumb Instructor.

Patch and Dollar Industry.

Patches And Decals Included.

Pissed-off Another Dive Instructor.

The largest certifying agency in the U.S.A.
PDICProfessional Diving Instructors Corporation. Certifying agency.
PFOPatent Foramen Ovale, openable flap between atria. See ASD. A shunt between the right and left side of the heart that allows some blood to circulate back through the body without going to the lungs first. This means that micro-bubbles don’t get removed from the blood stream by the lungs efficiently, making DCS more likely. 1in 4 people have a PFO.
Paul Bert EffectCNS O2 toxicity






NOAA – CNS oxygen toxicity exposure limits

ppO2 (Bar)

Exposure Limit per dive(min)

Exposure Limit per day (min)

1.6

1.5

1.4

1.3

1.2

1.1

1.0

0.9

0.7

45

120

150

180

210

240

300

360

570

150

180

180

210

240

270

300

360

570


PDCPersonal Dive Computer (British)
persuaderAny large crowbar, pipe wrench or sledge hammer used for souvenir hunting
pony bottle15 to 30 cu. ft. tank, typically worn beside main tank, as a fully redundant emergency air supply.
ppPartial Pressure. The total pressure of a gas mixture is the sum of the partial pressures of the component gases.
ppHePartial Pressure of Helium
ppO2
Partial Pressure of Oxygen. Don’t go over 1.4 ATA while diving, or over 1.6 ATA while decompressing.
ppN2Partial Pressure of Nitrogen
pretzelas in bent as a pretzel. Very bent, doubled over in agony.
primaryIn a Hogarth rig, the regulator with the long hose, wrapped around the canister light
on the right of your harness belt, up to the left of your head, around your neck and into your mouth.
psipounds per square inch. psi / 14.50377 = bar.
P weightWeight designed to fit in the gully of a standard backplate.

Q

R
reduce the signal-to-noise ratioWrite useless verbiage (noise), thereby reducing the proportion of useful postings (signal) to useless postings (noise).
RIBRigid Inflatable Boat, solid keel and large inflated tubes. (British)
riding the hookHooking up to a wreck by handing a diver the anchor and chain and said diver jumping over and riding it down to the wreck. Used for small/low-profile wrecks.
rolling a tankTumbling a tank to remove internal corrosion.
Rule #1Don’t dive with strokes. (Hogarthian)
Rule #2Don’t listen to strokes. (Hogarthian)
Rule of ThirdsAir – a third to get there, a third to get back, and last third belongs to your buddy.

S
SAASub Aqua Association. The thorn in BSAC‘s side, and the only thing stopping them from gaining world domination (well, err…in the UK at least).
SACSurface Air Consumption.

SAC = At Depth Air Consumption / At Depth Absolute Pressure

S.A.F.E.PADI training acronym: “Slowly Ascend From Every dive”. Alt: “Submerge And Forget Everything”.
safe secondOctopus.
SAR teamSearch and Rescue Team
ScooterDPV.
SCUBASelf Contained Underwater Breathing Apparatus. Contrast with SCBA, used by firefighters, which is similar but not intended for use underwater. Also compare with surface supplied air. Scuba is generally used to mean open circuit scuba, as opposed to closed or semi-closed circuit rebreathers.
SDShort for “Spare Death”, a slur on the brand name Spare Air. A can of air that is too small to get you to the surface in a real emergency.
sea liceYucky rash, actually caused by larvae of thimble jellyfish larva, getting trapped in bathing costume/lycra etc. and stinging. The larvae almost invisibly small.
secondIn a Hogarth rig, the regulator under your chin.
serious bandwidth-damagePosting of lots of stupid messages.
set the hookTo make sure that the wreckhook is securely fastened to the wreck. Usually done by the first person down.
shoot a bagTo send a liftbag up with a line attached for a floating deco.
silt-outComplete loss of vision caused by silt being disturbed, typically by careless finning.
SISurface Interval (between dives)
six-pack/fast boatSmall, open diveboat. Passengers generally limited to not more than six – ergo 6 pack.

In the USA a licensed captain can operate a boat carrying up to 6 paying passengers without
the boat undergoing the rigorous inspection required of vessels that carry more passengers.
Most dive boats tend to be either six packs less than 25 feet long or cattle boats of more than 40 feet.
The six packs still have to be seaworthy and must carry certain safety gear, they just don’t have to meet all the requirements that cruise ships do.

skinLycra for warm-water wimps.
sledWooden board you hold onto while being dragged by a boat.
sling [bottle]Stage bottle.
slobitusDCS skin hit (called that because it originates in fatty tissues).
sloppySnotty (New York/New Jersey).
snottyRough sea conditions. In the Northeast, this means 14 foot seas. In Cozumel, it means 2 inch seas.
SMBSurface Marker Buoy. Buoy with flag (on a line to diver). (British)
SOBSame Ocean Buddy
shot lineA weight with line and buoy attached to mark the location of a wreck. Used primarily by european divers.
‘sorbStuff in a rebreather to absorb the carbon dioxide you breathe out. Adsorbent.
souvenirTo remove items from a wreck.
SPGSubmersible Pressure Guage
spring strapsStainless steel springs used to hold your fins on your feet.
square diveA dive where you stay at the deepest point for the duration of the dive.
stabstabilizer jacket, or BC (British).
stage bottleA separate gas supply which is detachable from the diver.
steel 72Somewhat old-fashioned tank. Nominal capacity 72 cu. ft.
stopif it weren’t for the honor of the thing, the safety stop would be a deco stop
stroke (1)diver who’s so clueless that he/she is a danger to him/herself and anyone nearby. Often considered an accident looking for a place to happen.
stroke (2)Diver who refuses to learn even when shown a better way.
stroke (3)Favorite insult of Hogarthian divers at WKPP.
stroke mixWKPP divers believe that 80/20 is a bad idea, and refer to it as “stroke mix”.
strokeryThe practices of a stroke.
squidgieA RIB. (British)
suicide clipsA type of brass clip with a springed gate notorious for trapping lines and killing divers.

T
tag lineGranny line.
tankbottle
techalso tek, tekkie, techie, and cowboy
Techdiver SaluteA raised fore-finger indicating all is well.
thermoclineBoundary between layers of water of different temperatures.
tie inTo attach the wreck hook to the wreck with a separate line.
top-to-bottomUnderwater vis so good you can see the wreck from the surface.
towfishSide-scan sonar transducer. Towed in water behind boat.
toxSlang for central nervous system oxygen toxicity that can happen when diving too deep on air or diving deeper than you should on an enriched air (nitrox) mixture. Also called the Paul Bert Effect, but tox is easier to remember and lots easier to type.
travel mixMix such as 50/50 used to travel to or from the bottom. Travel gas is used to get down to the point where depth indicates that you must change to your bottom mix, and then to get up from that point to where you can switch to your deco mix(es).
trimixBreathing mix of three gases, typically oxygen, helium, and nitrogen. Composition is quoted as percentage of oxygen / percentage of helium, e.g. 17/50 is a trimix with 17% oxygen, 50% helium, balance (33%) nitrogen.
tumbleClean tanks of internal corrosion, by filling them with an abrasive such as ceramic chips or aluminum oxide, and leaving on a machine that rotates them for several hours.
TUPTransfer Under Pressure. A TUP system mates a portable
compression chamber to another chamber to transfer a person under
pressure from one chamber to the other.
TupperwareLarge plastic containers wreck divers use to haul all their gear.

U
undeserved hitDCS occuring despite staying within table or computer limits.

V
vaporwareSoftware that has been announced, but does not yet exist. Often pre-announced for
marketing reasons, to discourage users from purchasing a real, shipping, competitive product.
VIPVisual Inspection Program. Testing tank for integrity by visual inspection of insides.
vizVisibility. As in “viz was great – 15 to 20 feet” (North East wreck diver), or “viz was disgusting – 50 feet” (Florida tourist diver).
V weightV-shaped lead weight designed to fit between your tanks behind your backplate.

W
wah-wahsExtreme form of nitrogen narcosis (and possibly oxygen toxicity), described in Cautionary Tales.
weight retainerSmall metal or plastic device used to keep lead weights from sliding, among other things.
wetMeans more to us than just moisture present.
whipAdapter to fill tanks from O2 or He bottles.
WKPPWoodsville-Karst Plains Project
WPBWest Palm Beach
wreck hookAn anchor with bendable tines, also called a grappling hook.

X

Y
y valveTank valve with two outlets.

Z
zodiacA RIB.