Synonyms for Thirstiness (same or very similar meaning)
WordNet sense 1 (a deficiency of moisture (especially when resulting from a permanent absence of rainfall)):
aridity, aridnessWordNet sense 2 (a physiological need to drink):
thirstWordNet sense 3 (strong desire for something (not food or drink)):
hunger, hungrinessFrom the ODE community, based on WordNetadd/edit