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underdress

American  
[uhn-der-dres, uhn-der-dres] / ˌʌn dərˈdrɛs, ˈʌn dərˌdrɛs /

verb (used without object)

underdressed, underdrest, underdressing
  1. to clothe oneself less completely or formally than is usual or fitting for the circumstances.


noun

  1. garments worn beneath others; underclothes.

  2. a slip, petticoat, or other underskirt, especially one designed to be seen when worn, as beneath a redingote.

Etymology

Origin of underdress

First recorded in 1775–85; under- + dress