frow vs mulier

frow

noun
  • A woman; a wife, especially a Dutch or German one. 

  • A cleaving tool with handle at right angles to the blade, for splitting cask staves and shingles from the block; a frower. 

adj
  • Brittle; tender; crisp 

mulier

noun
  • Lawful issue born in wedlock, in distinction from an elder brother born of the same parents before their marriage. 

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