death-watch beetle vs woodworm

death-watch beetle

noun
  • A woodboring beetle, namely a beetle whose larvae are xylophagous. 

woodworm

noun
  • Any of many beetle larvae that bore into wood. 

  • Anobium punctatum, the Common Furniture Beetle. 

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

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