speaking has 4 distinct synonyms spread across 2 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. Its one recorded opposite is nonspeaking.
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 utterance of intelligible speech
delivering an address to a public audience
“people came to see the candidates and hear the speechmaking”
capable of or involving speech or speaking
“human beings--the speaking animals”
Synonyms, antonyms and the broader and narrower relations for speaking come from Princeton University’s WordNet. Full sources and licences.