sober has 9 distinct synonyms spread across 5 of its 7 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 intoxicated.
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.
not affected by a chemical substance (especially alcohol)
cause to become sober
“A sobering thought”
Synonyms, antonyms and the broader and narrower relations for sober come from Princeton University’s WordNet. Full sources and licences.