bathrobe vs tunic

bathrobe

noun
  • A robe usually made of terrycloth intended to be worn when one is still damp from bathing or when there is no immediate need to dress fully. 

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 bathrobe and tunic occurred in a corpus of books? (source: Google Ngram Viewer )