grammatical vs orthoepic

grammatical

adj
  • Of or pertaining to grammar. 

  • Not breaching any constraints of the grammar, or morpho-syntax, of the relevant language. 

orthoepic

adj
  • Synonym of phonological: concerning the study of pronunciation. 

  • Correctly or accurately pronounced. 

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