perturbation vs silence

perturbation

noun
  • Agitation; the state of being perturbed 

  • Variation in an orbit due to the influence of external bodies 

  • A small change in a physical system, or more broadly any definable system (such as a biological or economic system) 

silence

noun
  • The act of refraining from speaking. 

  • deadly silence 

  • The absence of any sound. 

intj
  • Be silent. 

verb
  • To repress the expression of something. 

  • To suppress criticism, etc. 

  • To block gene expression. 

  • To murder. 

  • To make (someone or something) silent. 

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