bimolecular

from WordNet (r) 3.0 (2006)

bimolecular
    adj 1: relating to or affecting two molecules

from The Collaborative International Dictionary of English v.0.48

bimolecular \bi"mo*lec"u*lar\, a. [Pref. bi- + molecular.]
   (Chem.)
   Pertaining to, involving, or formed from, two molecules; as,
   a bimolecular reaction (a reaction between two molecules).
   [Webster 1913 Suppl.]