maroon has 2 distinct synonyms spread across 2 of its 6 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. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
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.
a person who is stranded (as on an island)
“when the tide came in I was a maroon out there”
a dark purplish-red to dark brownish-red color
an exploding firework used as a warning signal
leave stranded on a desert island without resources
“The mutinous sailors were marooned on an island”
of dark brownish to purplish red
Synonyms, antonyms and the broader and narrower relations for maroon come from Princeton University’s WordNet. Full sources and licences.