lasting vs protean

lasting

noun
  • A durable woollen material formerly used for women's shoes. 

  • The act or process of shaping footwear on a last. 

adj
  • Persisting for an extended period of time. 

protean

noun
  • A protein that has been slightly modified by water, dilute acid, or enzymes, but not modified to the extent of a metaprotein. 

adj
  • Exceedingly variable; readily assuming different shapes or forms. 

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