mercantilism has 3 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.
an economic system (Europe in 18th century) to increase a nation's wealth by government regulation of all of the nation's commercial interests
transactions (sales and purchases) having the objective of supplying commodities (goods and services)
Synonyms, antonyms and the broader and narrower relations for mercantilism come from Princeton University’s WordNet. Full sources and licences.