a combining form of most occurring in a series of superlatives: foremost; utmost.
Origin of -most
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
forming the superlative degree of some adjectives and adverbshindmost; uppermost
Word Origin for -most
Old English -mǣst, -mest, originally a superlative suffix, later mistakenly taken as derived from mǣst (adv) most
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