abnormality vs divergence

abnormality

noun
  • The state or quality of being abnormal; variation; irregularity. 

  • Something abnormal; an aberration; an abnormal occurrence or feature. 

divergence

noun
  • The degree to which two or more things diverge. 

  • The process in which two or more populations accumulate genetic changes (mutations) through time. 

  • the operator which maps a function F=(F₁, ... Fₙ) from a n-dimensional vector space to itself to the function ∑ᵢ₌₁ⁿ(∂F_i)/(∂x_i) 

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