tremble vs waggle

tremble

verb
  • To shake, quiver, or vibrate. 

  • To fear; to be afraid. 

noun
  • A shake, quiver, or vibration. 

waggle

verb
  • To reel, sway, or move from side to side; to move with a wagging motion; to waddle. 

  • To move (something) with short, quick motions; to wobble. 

noun
  • A wobbling motion. 

  • The preliminary swinging of the club head back and forth over the ball in the line of the proposed stroke. 

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