treatment has 4 distinct synonyms spread across 3 of its 4 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.
care provided to improve a situation (especially medical procedures or applications that are intended to relieve illness or injury)
Synonyms, antonyms and the broader and narrower relations for treatment come from Princeton University’s WordNet. Full sources and licences.
the management of someone or something
“the handling of prisoners”
a manner of dealing with something artistically
“his treatment of space borrows from Italian architecture”
an extended communication (often interactive) dealing with some particular topic
“the book contains an excellent discussion of modal logic”