irritable; touchy; peevish
Origin of testyMiddle English testif ; from Anglo-French ; from Old French teste, the head ; from Classical Latin testa: see test
Irritated, impatient, or exasperated; peevish: a testy cab driver; a testy refusal to help.
Origin of testyAlteration of Middle English testif, headstrong, alteration (influenced by Middle English -if, variant of -ive, -ive, as in natif, native) of Old French testu, from Old French teste, head, from Late Latin testa, skull; see teston.
(comparative testier, superlative testiest)