WordNet (r) 3.0 (2006):

heterosexual
    adj 1: sexually attracted to members of the opposite sex [ant:
           bisexual, homosexual]
    n 1: a heterosexual person; someone having a sexual orientation
         to persons of the opposite sex [syn: heterosexual,
         heterosexual person, straight person, straight]

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "heterosexual":
   amorous, carnal, erogenic, erogenous, erotic, erotogenic, fleshly,
   gamic, libidinal, nuptial, oversexed, potent, procreative, sensual,
   sex, sexed, sexlike, sexual, sexy, straight, undersexed, venereal,
   voluptuous