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Glossary of Freediving Terms

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Deeper Blue Beachcomber
Nov 23, 2002
Hi Folks,
I've been visiting lately and am fascinated by all the information and people on the deeprblue forums. I mean it! This is a really inspiring forum.

As a newbie it would be interesting to be familiar with some of the terms used in freediving. I know most but sometimes am a bit lost with some of the more technical aspects of biochemistry or medical terms.

This would also be appreciated by those who don't have English as their first language so I propose that the editors create a webpage of all the different possible terms, and post them along with their definitions.

Any suggestions?

regards to all from (today) sunny Spain.


Jan. 29: Version 2 is here:

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110 terms so far

I've found around 110 terms so far from (supreficially) browsing the forum. There are still more out there waiting to be fished. Please add on any which are important and missing. I'll keep working on it. Some may seem very basic but I've added them for the sake of those not familiar with English.

I have them on an excel file that I can email to anyone who wants a copy. It's easy to keep in alphabetical order avoiding duplications. Any one who wants to contribute can just tack their terms on and we can merge all the files say, on a certain date.


air flash
ascent bo
ascent rates
blood PH
blood volume
bottom time
Breathing Oxygen
certifying agencies
clooged ear
CO2 tolerance
collapsed lung
constant ballast
constant weight
countdown time
DEMA Dive Show
depth adaptation
dive computers
dry static
dynamic apnea
ear fear
ear jamming
empty lung
exhale static
fluid buildup
fluid goggles
free ascent dangers
freediving tables
Frenzel Technique
heavy packing
hemoglobin level recovery
hemoglobin saturation
HMS Dolfin
hyperbaric oxygen therapy
ice freediving
lactic acid
lung capacity
lung fluid
lung squeeze
lung training
lung volume
mask air
mask volume
negative pressure dives
nitrogen narcossis
no limits
O2 levels
oxygen toxicity
pack stretching
personal bests
pipe mask
Raynaud's phenomenon
recreational freediving
residual lung volume
security rope
shallow water blackout
solo freediving
static apnea
surface intervals
tearduct equalization
variable ballast
warm ups
weight belt ditching
wet lungs
Good idea mate, that'd be darn handy... do you want us to send you definitions, or words that we want definitions for?
Great idea! We'll take a look and see if we can get a proper glossary up on the site.

Hi loopy and Stephen,

sure, just send any word or concept that you think would be useful and that you haven't seen on the list yet. That includes definitions. Everybody's welcome. The more the merrier.

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that is a champion Idea !! im a new head to free diving myself and would really appreciate something like that :)

Hey Adrian, spain is a beautiful country, your lucky to live there. i just hope that oil spill isnt wrecking everything for you..

oil spill

Hi Macker,
Luckily I live on the Mediterranean (northeast coast) just south of France. Great diving area. The oil spill is on the atlantic west coast of the country and covers more than 900 km of rocky coast and beautiful beaches, putting thousands of fishermen and women out of work as it is a very important shellfish producing area. Imagine half or more of Ireland's beautiful coastline lined in black. A real disaster and there's more oil floating around. There's lots of solidarity though with thousands of volunteers halping ckean the beaches and rocks.

I hope to get to writing up the definitions soon! :)


PS, My girlfriend's mad about Ireland, one day I'll make it over.
sombody post when this glossary is up cause im in desperate need. I know nothing, but really want to learn.
Rough draft of freediving terms

Taking advantage of a quiet Christmas I've made a rough draft of freediving terms and their definitions. Some of you will see your words paraphrased or almost verbatim from posts I've used as sources for definitions, others I've taken from dictionaries and the rest were written on the fly.

Any additions/revisions will be appreciated especially for the medical and more technical terms. And if you see that a particular term can be made to relate better to freediving add that as well! Please make any changes in another color so I can see them easily.

It is in a .doc format (76K) with about 140 terms :)wave You can find it here:


:wave )

Remember - the intelligence of the group is much greater than the intelligence of the individual so your input will be useful. This is a start and who knows, maybe we can end up creating an encyclopedia of freediving.

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extra input

collapsed lung.... this term isn't normally used to describe the state of the lung at extreme depth. see pneumothorax.
this may be referring to atelectasis which is the total collapse of alveoli (not the entire lung).

fire breathing... I think this is fancy term for hyperventilation

O2 levels... typo mistaje?.... correponds to O2 levels, not CO2, or vice versa?

PaCO2..... specifically arterial CO2

TLC......"The volume of air one can maximally inhale" makes it hard to distinguish from VC. TLC is just total lung volume -no more explanation needed in my opinion? you could say it's the sum of RV and VC to help distinguish it from VC.

this is a great idea. well done for all the effort! it would be nice to see it posted on DB somewhere soon.


Thanks Alun,
I've made the corrections you mentioned, did a search on "collapsed lung" and found out more. I never though I'd find out so much about physiology by joining DeeperBlue!

The attachment on my previous post has the new corrections.


Whoops:duh I don't know what I did, I deleted the old attachment from the earlir post and thought I could add a new one, but I can't find the button that lets me do so! The next post will have the changes.
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Great idea Adrian. I'm new to freedivng myself and this will help me to not ask so many stupid questions.:)
Hi Bindlestitch,
There's a saying, (perhaps by Mark Twain, it seems like something he would say) that goes: "It's better to keep your mouth shut and appear stupid than to open it and remove all doubt!"

In the case of freediving it's much wiser to open your mouth and ask all the questions you want because of the safety factor. Maybe a little bit of knowledge will help you out allot later when you need it. Besides, the people on this list are open and won't hesitate to help you out. Freediving is one of the sports where competitors actually encourage each other to surpass their limits. Pretty healthy attitude and goes with the nature of openness and freedom of freediving. :)

Fire Breathing is a form of Pranayama, or Yoga-breathing .....

Do a search on the site if you want to know more about it - there's a pretty interesting thread on it somewhere ...
Tear Duct Equalisation?

thanks for the list - was doing fine til I got to T..

Tear Duct Equalisation??? how on earth......

my eyes are bleeding just thinking about it

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I´ve seen on TV once a girl that could inflate a balloon through her tearducts... incredible!!!
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I've seen a guy put milk up his nose and squirt it out of his tear ducts.:waterwork
a mate of mine has just told me he equalises his mask by blowing out through his tear ducts... anyone know why some people can do it and others not?
Tear Duct Eqalization

I couldn't say why, but that it happens to my left tearduct when one of my ears gets clogged up. It's kind of frustrating, I want the air to go the other way!

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