Dictionary
col•lab•o•rate
Pronunciation: (ku-lab'u-rāt"), [key]—
v.i., -rat•ed, -rat•ing.
1. to work, one with another; cooperate, as on a literary work:
They collaborated on a novel.
2. to cooperate, usually willingly, with an enemy nation, esp. with an enemy occupying one's country:
He collaborated with the Nazis during World War II. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.