The Collaborative International Dictionary
Bimestrial
Bimestrial \Bi*mes"tri*al\, a. [L. bimestris; bis twice + mensis month.] Continuing two months. [R.]
Wiktionary
bimestrial
a. Occurring once every two month
WordNet
bimestrial
adj. occurring every two months; "bimonthly visits" [syn: bimonthly]
two months long; lasting two months