doddering vs tremble

doddering

noun
  • A shaking or trembling movement, as of old age. 

adj
  • mentally or physically infirm due to old age; senile 

tremble

noun
  • A shake, quiver, or vibration. 

verb
  • To shake, quiver, or vibrate. 

  • To fear; to be afraid. 

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