anaerobe

[an-uh-rohb, an-air-ohb] /ˈæn əˌroʊb, ænˈɛər oʊb/
noun
1.
an organism, especially a bacterium, that does not require air or free oxygen to live (opposed to aerobe).
Origin
1875-80; an-1 + aerobe
British Dictionary definitions for anaerobe

anaerobe

/æˈnɛərəʊb; ˈænərəʊb/
noun (pl) -obes, -obia (-ˈəʊbɪə)
1.
an organism that does not require oxygen for respiration Compare aerobe
anaerobe in Medicine

anaerobe an·aer·obe (ān'ə-rōb', ān-âr'ōb')
n.
An organism that can live in the absence of atmospheric oxygen.

anaerobe in Science
anaerobe
  (ān'ə-rōb')   
An organism, such as a bacterium, that can or must live in the absence of oxygen. Compare aerobe.