cooperative has 5 distinct synonyms spread across 3 of its 5 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. Its one recorded opposite is uncooperative.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
done with or working with others for a common purpose or benefit
“a cooperative effort”
willing to adjust to differences in order to obtain agreement
a jointly owned commercial enterprise (usually organized by farmers or consumers) that produces and distributes goods and services and is run for the benefit of its owners
an association formed and operated for the benefit of those using it
Synonyms, antonyms and the broader and narrower relations for cooperative come from Princeton University’s WordNet. Full sources and licences.