Merriam-Webster Collegiate Dictionary - thirst

 I. noun  Etymology: Middle English, from Old English thurst; akin to Old High German durst ~, Latin torrere to dry, parch, Old Irish tart dryness, ~, Greek tersesthai to become dry  Date: before 12th century  1.  a. a sensation of dryness in the mouth and throat associated with a desire for liquids; also the bodily condition (as of dehydration) that induces this sensation  b. a desire or need to drink  2. an ardent desire ; craving, longing a ~ for success  II. intransitive verb  Date: before 12th century  1. to feel ~y ; suffer ~  2. to crave vehemently and urgently  Synonyms: see long  • ~er noun