dressing gown vs workwear

dressing gown

noun
  • An item of clothing often made from cotton or another absorbent material, in the form of a long open robe with a belt to tie it around the middle and fasten it securely; often worn over pyjamas. 

workwear

noun
  • Clothes designed to be worn while working, especially in a physically demanding job. 

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