The Collaborative International Dictionary of English v.0.48:
Acarpellous \Ac`ar*pel"lous\, acarpelous \ac`ar*pel"ous\, a. [Pref. a- not + carpel.] (Bot.) Having no carpels. Opposite of carpellate. Syn: acarpe [1913 Webster]WordNet (r) 3.0 (2006):
acarpelous adj 1: having no carpels [syn: acarpelous, acarpellous] [ant: carpellate, pistillate]