Anaerobic is a technical word which literally means without air, as opposed to aerobic. The presence or absence of air, or more precisely the presence or absence of oxygen in the air, affects various chemical and biological reactions.

One example is that wood which is totally immersed in water does not rot - rotting being a process requiring water and oxygen - see Seahenge.

See also:

• Anaerobic exercise
• Anaerobic glycolysis
• Anaerobic metabolism
• Anaerobic organism
• Anaerobic respiration
• oxygen depletion