treasure has 8 distinct synonyms spread across 4 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.
accumulated wealth in the form of money or jewels etc.
“the pirates hid their treasure on a small island in the West Indies”
any possession that is highly valued by its owner
“the children returned from the seashore with their shells and other treasures”
a collection of precious things
“the trunk held all her meager treasures”
hold dear
“I prize these old photographs”
be fond of; be attached to
Synonyms, antonyms and the broader and narrower relations for treasure come from Princeton University’s WordNet. Full sources and licences.