Wordnet 3.0
NOUN (1)
1. 
 a contraceptive in the form of a pill containing estrogen and progestin to inhibit ovulation and so prevent conception; 
[syn: pill, birth control pill, contraceptive pill, oral contraceptive pill, oral contraceptive, anovulatory drug, anovulant]
WordNet (r) 3.0 (2006):
anovulatory drug
    n 1: a contraceptive in the form of a pill containing estrogen
         and progestin to inhibit ovulation and so prevent
         conception [syn: pill, birth control pill,
         contraceptive pill, oral contraceptive pill, oral
         contraceptive, anovulatory drug, anovulant]