Aerotaxis \A"["e]r*o*tax`is\, n. [NL. See {A["e]ro-}; {Taxis}.] (Bacteriology) The positive or negative stimulus exerted by oxygen on a["e]robic and ana["e]robic bacteria. -- {A`["e]r*o*tac"tic}, a. [Webster 1913 Suppl.]