excellent vs optimal

excellent

adj
  • Of higher or the highest quality; splendid. 

  • Having excelled, having surpassed. 

  • Superior in kind or degree, irrespective of moral quality. 

  • Exceptionally good of its kind. 

optimal

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

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

noun
  • The best of its kind 

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