Etymology
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frowzy (adj.)
also frowsy, 1680s, possibly related to dialectal frowsty (q.v.).
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frowsty (adj.)
"having an unpleasant smell," 1865, of unknown origin; perhaps related to Old French frouste "ruinous, decayed," or to Old English þroh "rancid;" both of which also are of uncertain origin. Also compare frowzy.
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