Third-person singular simple present indicative form of undress.(verb)
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Use "undresses" in a sentence
"Frank Careless, as soon as his valet has helped on and adjusted his clothes, goes to his glass, sets his wig awry, tumbles his cravat; and in short, undresses himself to go into company."
"The Travel Channel unveils (or maybe I should say "undresses") a new show on Thursday at 10 p.m."
"Nobody undresses better than Anna's almost-traitorous offspring Lisa."