say it: koh-AH-pur-ayt
cooperate is a verb meaning "work together on a common enterprise of project". It carries one recorded sense.
work together on a common enterprise of project
“The soprano and the pianist did not get together very well”
“We joined forces with another research group”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for cooperate come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.