tremble vs vellicate

tremble

verb
  • To shake, quiver, or vibrate. 

  • To fear; to be afraid. 

noun
  • A shake, quiver, or vibration. 

vellicate

verb
  • To twitch or move convulsively. 

  • To touch (a body part) lightly so as to excite the surface nerves and cause uneasiness, laughter, or spasmodic movements. 

  • To tickle, provoking twitching and laughter. 

  • To criticize in a somewhat irritating way; to carp at. 

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