Origin: before 900; Middle English thirsten (v.), Old English thyrstan, derivative of thurst (noun); cognate with Dutch dorst,German Durst,Old Norse thorsti,Gothic thaurstei; noun has -i- from the v. or from thirsty; see toast1
O.E. þurst, from W.Gmc. *thurstus (cf. O.S. thurst, Fris. torst, Du. dorst, O.H.G., Ger. durst), from P.Gmc. *thurs-, from PIE base *ters- "dry" (see terrain). Fig. sense of "vehement desire" is attested from c.1200. The verb is O.E. þyrstan; the fig. sense of