The Collaborative International Dictionary of English v.0.48:
Bisect \Bi*sect"\, v. t. [imp. & p. p. Bisected; p. pr. & vb. n. Bisecting.] [L. bis twice + secare, sectum, to cut.] 1. To cut or divide into two parts. [1913 Webster] 2. (Geom.) To divide into two equal parts. [1913 Webster]WordNet (r) 3.0 (2006):
bisect v 1: cut in half or cut in two; "bisect a line"