eye dialect vs subdialect

eye dialect

noun
  • A set of such nonstandard spellings, collectively used to reflect a certain form of speech. 

  • Nonstandard spellings which, although they indicate a standard pronunciation, are deliberately substituted in place of the standard spellings, often to indicate that a speaker's regular use of language is nonstandard or dialectal. 

subdialect

noun
  • A subdivision of a dialect 

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