gather has 17 distinct synonyms spread across 8 of its 11 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 spread.
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.
collect or gather
“Journals are accumulating in my office”
conclude from evidence
“I gather you have not done your homework”
draw and bring closer
“she gathered her shawl around her shoulders”
the act of gathering something
Synonyms, antonyms and the broader and narrower relations for gather come from Princeton University’s WordNet. Full sources and licences.