1. 
[syn: asexual, nonsexual]
The Collaborative International Dictionary of English v.0.48:
Asexual \A*sex"u*al\ (?; 135), a. [Pref. a- not + sexual.]
   1. (Biol.) Having no distinct sex; without sexual action; as,
      asexual reproduction. See Fission and Gemmation.
      [1913 Webster]
   2. not involving sexual activity or sexual attraction; as, an
      asexual friendship.
      [PJC]
WordNet (r) 3.0 (2006):
asexual
    adj 1: not having or involving sex; "an asexual spore"; "asexual
           reproduction" [syn: asexual, nonsexual] [ant:
           sexual]