difference has 7 distinct synonyms spread across 3 of its 5 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 sameness.
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 quality of being unlike or dissimilar
“there are many differences between jazz and rock”
Synonyms, antonyms and the broader and narrower relations for difference come from Princeton University’s WordNet. Full sources and licences.
a variation that deviates from the standard or norm
“the deviation from the mean”
a disagreement or argument about something important
“he had a dispute with his wife”
a significant change
“the difference in her is amazing”