discretion has 6 distinct synonyms spread across 4 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.
freedom to act or judge on one's own
knowing how to avoid embarrassment or distress
“the servants showed great tact and discretion”
the power of making free choices unconstrained by external agencies
the trait of judging wisely and objectively
“a man of discernment”
Synonyms, antonyms and the broader and narrower relations for discretion come from Princeton University’s WordNet. Full sources and licences.