Meaning

adjective (superlative of `many' used with count nouns and often preceded by `the') quantifier meaning the greatest in number

adjective the superlative of `much' that can be used with mass nouns and is usually preceded by `the'; a quantifier meaning the greatest in amount or extent or degree

originEtymology tree Proto-Indo-European *meh₂-der. Proto-Germanic *maiz Proto-Germanic *maistaz Proto-Germanic *maist Proto-West Germanic *maist Old English mǣst Middle English English most Proto-Indo-European *-yōs Proto-Indo-European *-tHós Proto-Indo-European *-istHos Proto-Germanic *-istaz Proto-West Germanic *-ist Old English -est Middle English -est English -est English mostest From most + -est.

Etymology from Wiktionary, CC BY-SA 3.0