optimal vs stellar

optimal

adj
  • Describing a search algorithm that always returns the best result. 

  • The best, most favourable or desirable, especially under some restriction. 

noun
  • The best of its kind 

stellar

adj
  • Of, pertaining to, or characteristic of stars. 

  • Heavenly. 

  • Exceptional. 

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