parka vs tunic

parka

noun
  • A long jacket with a hood which protects the wearer against rain and wind. 

tunic

noun
  • A garment worn over the torso, with or without sleeves, and of various lengths reaching from the hips to the ankles. 

  • Any covering, such as seed coat or the organ that covers a membrane. 

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