shovel vs trephine

shovel

noun
  • A hand tool with a handle, used for moving portions of material such as earth, snow, and grain from one place to another, with some forms also used for digging. Not to be confused with a spade, which is designed solely for small-scale digging and incidental tasks such as chopping of small roots. 

  • A mechanical part of an excavator with a similar function. 

  • A spade. 

verb
  • To move materials with a shovel. 

  • To move with a shoveling motion. 

trephine

noun
  • A surgical instrument with a cylindrical blade used to remove a circular section of tissue, f.e. bone or cornea; a trepan. 

verb
  • To use a trephine during surgery. 

  • To perforate with a trephine. 

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