GNU Collaborative International Dictionary of English

Found one definition

1.       
   Testy (?), a. [Compar. Testier (?); superl. Testiest.] [OF. testu obstinate, headstrong, F. têtu, fr. OF. teste the head, F. tête. See Test a cupel.] Fretful; peevish; petulant; easily irritated.
   
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   Must I observe you? must I stand and crouch
   
   Under your testy humor? Shak.
   
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   I was displeased with myself; I was testy. Latimer.
   
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