international has 2 distinct synonyms spread across 1 of its 3 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 national.
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.
concerning or belonging to all or at least two or more nations
“international affairs”
any of several international socialist organizations
Synonyms, antonyms and the broader and narrower relations for international come from Princeton University’s WordNet. Full sources and licences.