non-gradable vs recherché

non-gradable

adj
  • (of an adjective) Describing a quality that cannot normally be varied because it is extreme (e.g. freezing), absolute (e.g. dead), or classification (e.g. nuclear). 

  • That cannot be graded. 

noun
  • Any adjective that is not gradable. 

recherché

adj
  • Of rare quality, elegance, or attractiveness, especially with an artificial or pretentious effect. 

  • Sought out and chosen with care. 

How often have the words non-gradable and recherché occurred in a corpus of books? (source: Google Ngram Viewer )