The practice of scuba divingThe scuba diving glossaryOur glossaries

Last updated on 02/03/2026 at 12:22 AM

English

Description

French

Français

anoxia

Définition

Severe lack of oxygen supply to the body (oxygen partial pressure below 0.12 bar).

Anglais

anoxie

Français

artery

Définition

Blood vessel that carries blood away from the heart to the body.

Anglais

artère

Français

BCD (Buoyancy Control Device)

Définition

Equipment worn by the diver to control buoyancy underwater, commonly called a buoyancy compensator or BCD for Buoyancy Control Device.

Anglais

gilet

Français

BCD / buoyancy compensator

Définition

Buoyancy control device (BCD) that allows the diver to manage underwater buoyancy by adjusting the air volume in the vest.

Anglais

stab / gilet stabilisateur

Français

buddy

Définition

Two divers paired together to monitor each other and ensure safety during a dive.

Anglais

binôme de plongée

Français

collapsus

Définition

Rapid loss of strength or collapse without fainting.

Anglais

collapsus

Français

controlled ascent

Définition

Slow, controlled ascent to the surface to prevent decompression sickness.

Anglais

remontée contrôlée

Français

decompression stop

Définition

Decompression stop performed during ascent at a specified depth to allow dissolved nitrogen in the body to be safely eliminated and prevent decompression sickness.

Anglais

palier

Français

dive computer

Définition

Wrist-worn electronic device that continuously monitors depth, dive time, decompression status, and air consumption, providing real-time guidance for safe scuba diving.

Anglais

ordinateur (de plongée)

Français

dive group

Définition

Group of divers conducting a dive together, usually led by a dive guide or instructor.

Anglais

palanquée

Français

EAN (Enriched Air Nitrox)

Définition

The term Nitrox (Enriched Air Nitrox, EAN) is a mixture of nitrogen and oxygen used in scuba diving to extend no-decompression limits.

Anglais

NITROX

Français

embolism

Définition

Blockage of a blood vessel by a foreign body, especially an air bubble in diving.

Anglais

embolie

Français

emphysema

Définition

Swelling caused by trapped air bubbles in body tissues.

Anglais

emphysème

Français

heliair

Définition

A breathing gas mixture of helium and air, also called Trimix lite or Poor Man's Trimix, used by deep-sea divers.

Anglais

héliair

Français

fin

Définition

Equipment worn on the diver's feet to enhance propulsion and movement underwater.

Anglais

palme

Français

pressure gauge

Définition

Instrument that measures the air pressure in the scuba cylinder or tank, allowing the diver to monitor air consumption.

Anglais

manomètre

Français

heliox

Définition

Helium-oxygen mixture used for deep scuba diving up to 130 meters.

Anglais

héliox

Français

High Pressure Nervous Syndrome (HPNS)

Définition

High Pressure Nervous Syndrome (HPNS) caused by helium toxicity at high pressures.

Anglais

SNHP

Français

hydreliox

Définition

Gas mixture of hydrogen, helium, and oxygen used for deep dives up to 300 meters.

Anglais

hydréliox

Français

hydrox

Définition

Gas mixture of hydrogen and oxygen used experimentally for ultra-deep diving.

Anglais

hydrox

Français

hyperbaric chamber

Définition

Sealed chamber used to simulate underwater pressure conditions to treat decompression sickness or for diver training.

Anglais

caisson

Français

hypoxemia

Définition

Low oxygen concentration in the body (partial pressure between 0.12 and 0.17 bar); below 0.12 bar, it is called anoxia.

Anglais

hypoxie

Français

red blood cell

Définition

Red blood cell responsible for transporting oxygen.

Anglais

hémathie

Français

jacket

Définition

Diving vest or buoyancy compensator worn by the diver to control buoyancy underwater.

Anglais

jacket

Français

leukocyte

Définition

White blood cell involved in immune defense.

Anglais

leucocyte

Français

lifeline / safety line

Définition

Rope or line secured to a safe point, used to guide the diver and ensure safety, especially in cave, wreck, or strong current diving.

Anglais

ligne de vie

Français

neoprene

Définition

Synthetic material used to make wetsuits, providing thermal insulation and flexibility underwater.

Anglais

néoprène

Français

regulator

Définition

Device that allows breathing underwater by reducing the high pressure of the air in the scuba tank to a breathable pressure for the diver.

Anglais

détendeur

Français

reserve air

Définition

Remaining air in the scuba tank set aside to ensure a safe ascent or to reach the exit point if needed.

Anglais

réserve

Français

diving suit / wetsuit / drysuit

Définition

Diving suit designed to protect the diver from cold, abrasions, and injuries, made of neoprene or similar materials, and can be wet (wetsuit) or dry (drysuit).

Anglais

combinaison

Français

filling station

Définition

Facility equipped to fill scuba tanks with compressed air or specialized breathing gas mixtures such as Nitrox or Trimix.

Anglais

station de gonflage

Français

snorkel

Définition

Tube allowing breathing at the water surface without lifting the head, used for snorkeling or as secondary equipment in scuba diving.

Anglais

tuba

Français

buffer tank

Définition

Reservoir cylinder used to temporarily store compressed air or a breathing gas mixture before transferring it into main scuba tanks.

Anglais

bouteille tampon

Français

scuba tank

Définition

Scuba tank containing compressed air or a breathing gas mixture (Nitrox, Trimix, …) used for scuba diving.

Anglais

bloc

Français

tachycardia

Définition

Abnormally fast heart rate.

Anglais

tachycardie

Français

tachypnea

Définition

Abnormally rapid breathing rate.

Anglais

polypnée

Français

thermogenesis

Définition

Production of heat by the body.

Anglais

thermogenèse

Français

thermolysis

Définition

Process of heat loss to eliminate excess body heat.

Anglais

thermolyse

Français

thermoregulation

Définition

Body system regulating heat production and loss to maintain a stable temperature.

Anglais

thermorégulation

Français

trimix

Définition

Technical diving gas mixture of nitrogen, helium, and oxygen.

Anglais

trimix

Français

valve

Définition

Valve installed on a scuba cylinder or tank that allows opening or closing the airflow to the regulator, controlling the supply of breathable gas.

Anglais

robinet

Français

vein

Définition

Blood vessel carrying blood to the heart.
Note: Veins are distinguished from arteries by the direction of blood flow relative to the heart.

Anglais

veine

Français

weight

Définition

Weight added to the diver or equipment to counteract buoyancy, enabling descent and stability underwater.

Anglais

plomb

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