The Collaborative International Dictionary of English v.0.48:
Quenchless \Quench"less\, a. Incapable of being quenched; inextinguishable; as, quenchless fire or fury. "Once kindled, quenchless evermore." --Byron. [1913 Webster] Syn: Inextinguishable; unquenchable. [1913 Webster] -- Quench"less*ly, adv. -- Quench"less*ness, n. [1913 Webster]WordNet (r) 3.0 (2006):
quenchless adj 1: impossible to quench; "unquenchable thirst" [syn: quenchless, unquenchable]