drill bit vs milling cutter

drill bit

noun
  • Any other style of cutter, for example a spade drill, that is rotated and fed in a similar manner as a twist drill to of cut a hole in metal, wood or other materials. 

  • A twist drill. 

milling cutter

noun
  • A rotary cutting tool typically used in milling machines. 

How often have the words drill bit and milling cutter occurred in a corpus of books? (source: Google Ngram Viewer )