English to English

verb (v)

• dress without sufficient warmth(verb.body)

  Example:
  She was underdressed for the hiking trip and suffered hypothermia.
  

  Antonym:
  overclothe, overdress
  

  source: wordnet30
• dress informally and casually(verb.body)

  Example:
  On Fridays, employees can underdress.
  

  Synonym:
  dress down
  Antonym:
  attire, deck out, deck up, dress up, fancy up, fig out, fig up, get up, gussy up, overdress, prink, rig out, tog out, tog up, trick out, trick up
  

  source: wordnet30