gravedigger vs woodworm

gravedigger

noun
  • A necrophore, or burying beetle. 

  • A person employed to dig graves. 

woodworm

noun
  • Anobium punctatum, the Common Furniture Beetle. 

  • Any of many beetle larvae that bore into wood. 

  • A shipworm, a worm-like mollusk in the family Teredinidae that feeds on wood underwater in saltwater. 

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