anaerobes

An*a`ër*o"bi*a, An*a"ër*obes, n. pl. [NL. anaerobia; an-not + aëro- + Gr. life.] (Bacteriol.) Defn: Anaërobic bacteria. They are called facultative anaërobia when able to live either in the presence or absence of free oxygen; obligate, or obligatory, anaërobia when they thrive only in its absence.

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