rich people has 1 distinct synonym spread across 1 of its 1 sense. 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 poor people.
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.
people who have possessions and wealth (considered as a group)
“only the very rich benefit from this legislation”
Synonyms, antonyms and the broader and narrower relations for rich people come from Princeton University’s WordNet. Full sources and licences.