1.Definition: an associate in an activity or endeavor or sphere of common interest

"The musician and the librettist were collaborators", "Sexual partners"

Related Noun(s):cooperator, pardner, partner

Category: People

2.Definition: someone who assists in a plot

Related Noun(s):confederate, henchman, partner in crime

Category: People

3.Definition: someone who collaborates with an enemy occupying force

Related Noun(s):collaborationist, quisling

Category: People