quiver vs wag

quiver

verb
  • To shake or move with slight and tremulous motion. 

noun
  • A multidigraph. 

  • A ready storage location for figurative tools or weapons. 

  • A container for arrows, crossbow bolts or darts, such as those fired from a bow, crossbow or blowgun. 

wag

verb
  • To swing from side to side, such as of an animal's tail, or someone's head, to express disagreement or disbelief. 

  • To play truant from school. 

noun
  • A witty person. 

  • An oscillating movement. 

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