Webster's Revised Unabridged Dictionary · 1913

Anaerobic

Anaerobic ({not transcribed}) , adjective

[Prefix an-not + aerobic.]

1.
(Biology) Not requiring air or oxygen for life; -- applied especially to those microbes to which free oxygen is unnecessary; anaerobiotic; -- opposed to aerobic.
2.
(Biology) Relating to, or like, anaerobies; anaerobiotic.