garment vs pair of underwear

garment

noun
  • A single item of clothing. 

  • The visible exterior in which a thing is invested or embodied. 

verb
  • To clothe in a garment. 

pair of underwear

noun
  • An item of clothing that is worn under one's trousers or pants. 

How often have the words garment and pair of underwear occurred in a corpus of books? (source: Google Ngram Viewer )