ageful vs emeritus

ageful

noun

  • An eternity, a perpetuity. 

adj

  • Eternal, everlasting. 

  • Aged, elderly, old. 

emeritus

noun

  • A person retired in this sense. 

adj

  • Retired, but retaining an honorific version of a previous title. 

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