The Collaborative International Dictionary of English v.0.48:
bimillenary \bimillenary\ n. a span of 2000 years. Syn: bimillennium. [WordNet 1.5]WordNet (r) 3.0 (2006):
bimillenary n 1: the 2000th anniversary (or the celebration of it) [syn: bimillennium, bimillenary] 2: a span of 2000 years [syn: bimillennium, bimillenary]