strangulation has 3 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. 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.
the act of suffocating (someone) by constricting the windpipe
“no evidence that the choking was done by the accused”
the condition of having respiration stopped by compression of the air passage
(pathology) constriction of a body part so as to cut off the flow of blood or other fluid
“strangulation of the intestine”
Synonyms, antonyms and the broader and narrower relations for strangulation come from Princeton University’s WordNet. Full sources and licences.