swirl vs tremble

swirl

verb
  • To twist or whirl, as an eddy. 

  • To be arranged in a twist, spiral or whorl. 

  • To circulate. 

noun
  • The upward rushing of a fish through the water to take the bait. 

  • A twist or coil of something. 

  • A whirling eddy. 

tremble

verb
  • To shake, quiver, or vibrate. 

  • To fear; to be afraid. 

noun
  • A shake, quiver, or vibration. 

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