confrontation has 4 distinct synonyms spread across 2 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. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
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.
discord resulting from a clash of ideas or opinions
a hostile disagreement face-to-face
Synonyms, antonyms and the broader and narrower relations for confrontation come from Princeton University’s WordNet. Full sources and licences.
the act of hostile groups opposing each other
“the government was not ready for a confrontation with the unions”
a focussed comparison; bringing together for a careful comparison