[verb uhn-der-dres; noun uhn-der-dres]
verb (used without object), un·der·dressed or un·der·drest, un·der·dress·ing.
  1. to clothe oneself less completely or formally than is usual or fitting for the circumstances.
  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.

Origin of underdress

First recorded in 1775–85; under- + dress
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for underdress

Historical Examples of underdress