1. 
[syn: anaerobic, anaerobiotic]
2.  not aerobic; 
- Example: "isometric exercises are anaerobic"
The Collaborative International Dictionary of English v.0.48:
Anaerobic \An*a`["e]*rob"ic\, a. [Pref. an-not + a["e]robic.]
   1. (Biol.) Not requiring air or oxygen for life; -- applied
      especially to those microbes to which free oxygen is
      unnecessary; ana["e]robiotic; -- opposed to a["e]robic.
      [Webster 1913 Suppl.]
   2. (Biol.) Relating to, or like, ana["e]robies;
      ana["e]robiotic.
      [1913 Webster]
WordNet (r) 3.0 (2006):
anaerobic
    adj 1: living or active in the absence of free oxygen;
           "anaerobic bacteria" [syn: anaerobic, anaerobiotic]
           [ant: aerobic, aerophilic, aerophilous]
    2: not aerobic; "isometric exercises are anaerobic" [ant:
       aerobic]