Definition of "underdress" [underdress]

• Apparel worn beneath outer garments; underclothing. (noun)
• An outer garment, such as a dress beneath a tunic or coat, that is worn as part of a costume or suit. (noun)
• To dress too informally for the occasion. (verb-intransitive)
• To dress without sufficient warmth: You're underdressing that baby for such a cold day. (verb-intransitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "A severely plain underdress of heavy white satin formed the foundation."
• "I still remember how pretty and vibrant those over dresses were, with the underdress."
• "I'm also wondering if that was possibly done as an alternative to wearing an apron, since with the hem folded up like that any dirt would then fall on the underside of the dress or on the petticoat/underdress, and then once the chore was finished the hem could be let down again and the dirt is not visible."