conductor has 2 distinct synonyms spread across 1 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. Its one recorded opposite is insulator.
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 person who leads a musical group
a substance that readily conducts e.g. electricity and heat
the person who collects fares on a public conveyance
Synonyms, antonyms and the broader and narrower relations for conductor come from Princeton University’s WordNet. Full sources and licences.