A sensation of dryness in the throat associated with a craving for liquids, produced by deprivation of drink, or by some other cause (as fear, excitement, etc.) which arrests the secretion of the pharyngeal mucous membrane; hence, the condition producing this sensation.
source: Webster 1913
verb
feel the need to drink
source: WordNet 3.0
have a craving, appetite, or great desire for
source: WordNet 3.0
To feel thirst; to experience a painful or uneasy sensation of the throat or fauces, as for want of drink.