Bi: prefix, means two.
Bi-alar: two-winged; applied to Diptera.
Biarcuate: twice curved.
Biareolate: with two cells or areoles: see bilocular.
Bicaudate: having two tails or anal processes.
Bicolored: with two colors that contrast to some extent.
Bicornute: with two horns or cephalic processes.
Bicuspidate: ending in two points or cusps.
Bidactylate: with two fingers or finger-like processes.
Bidentate: two-toothed.