milch cow vs milker

milch cow

noun
  • A cow kept for milking; a dairy cow. 

  • A cash cow. 

  • A cow that produces milk (having had at least one calf). 

  • A German WWII submarine designed to carry large cargoes of supplies and transfer them to other submarines. 

milker

noun
  • An animal, such as a dairy cow, kept for the milk it produces. 

  • A woman’s breast. 

  • A milking machine. 

  • A person who milks. 

  • A conservative poker player who only raises the stakes on a good hand. 

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