Definition from Wiktionary, the free dictionary
- To work together with others to achieve a common goal.
- Let's collaborate on this dictionary, and get it finished faster.
- To voluntarily cooperate treasonably, as with an enemy occupation force in one's country.
- If you collaborate with the occupying forces, you will be shot.
to work together on a piece of work
to cooperate treasonably
- “collaborate” in The American Heritage® Dictionary of the English Language, Fourth Edition, Houghton Mifflin Company, 2000.
- “collaborate” in Dictionary.com Unabridged, v1.0.1, Lexico Publishing Group, 2006.
- "collaborate" in the Kernerman English Multilingual Dictionary (Beta Version), K Dictionaries limited, 2000-2006.
- "collaborate" in WordNet 3.0, Princeton University, 2006.
Verb form 
- second-person plural present tense of collaborare
- second-person plural present subjunctive of collaborare
- second-person plural imperative of collaborare
- second-person plural present active imperative of collabōrō