explanation vs outgrowth

explanation

noun
  • The act or process of explaining. 

  • Something that explains, makes understandable. 

  • A resolution of disputed points pursuant to discussion; a mutual clarification of disputed points; reconciliation. 

outgrowth

noun
  • A byproduct or consequence of an action or event. 

  • An appendage of an animal. 

  • A branch or offshoot of a plant. 

  • Excessive growth. 

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