divergence vs irregularity

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) 

irregularity

noun
  • An instance of being irregular. 

  • A violation of rules. 

  • An object or event that is not regular or ordinary. 

  • Irregular bowel movement (e.g. diarrhea or constipation). 

  • The state or condition of being irregular, or the extent to which something is irregular. 

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