inhale has 2 distinct synonyms spread across 1 of its 2 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 exhale.
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.
draw deep into the lungs in by breathing
“Clinton smoked marijuana but never inhaled”
Synonyms, antonyms and the broader and narrower relations for inhale come from Princeton University’s WordNet. Full sources and licences.