byproduct vs outgrowth

byproduct

outgrowth

noun
  • An appendage of an animal. 

  • A branch or offshoot of a plant. 

  • Excessive growth. 

  • A byproduct or consequence of an action or event. 

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