monomorphic vs multiform

monomorphic

adj
  • having or existing in a single shape or form 

  • taking only a single data type 

  • invariant across a species 

multiform

adj
  • Having more than one shape or appearance. 

noun
  • An organism, folktale, etc. that appears in more than one form. 

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