half-slip vs kirtle

half-slip

kirtle

noun
  • A knee-length tunic. 

  • A woman's gown; a woman's outer petticoat or skirt. 

  • A short jacket. 

verb
  • To clothe or cover with, or as if with, a kirtle; to hitch up (a long garment) to the length of a kirtle. 

How often have the words half-slip and kirtle occurred in a corpus of books? (source: Google Ngram Viewer )