champlain has 2 distinct synonyms spread across 2 of its 2 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.
French explorer in Nova Scotia who established a settlement on the site of modern Quebec (1567-1635)
a lake in northeastern New York, northwestern Vermont and southern Quebec; site of many battles in the French and Indian War and in the American Revolution and in the War of 1812
Synonyms, antonyms and the broader and narrower relations for champlain come from Princeton University’s WordNet. Full sources and licences.