Antonyms for Most (opposite meaning)
WordNet sense 1 ((superlative of `few' used with count nouns and usually preceded by `the') quantifier meaning the smallest in number):
fewest
WordNet sense 2 (the superlative of `little' that can be used with mass nouns and is usually preceded by `the'; a quantifier meaning smallest in amount or extent or degree):
least
From the ODE community, based on WordNet
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