dedicatory vs initiatory

dedicatory

adj

  • Of or pertaining to dedication. 

noun

  • A dedication. 

initiatory

adj

  • Of or pertaining to initiation 

  • inceptive, initial, inaugural or introductory 

noun

  • An introductory act or rite. 

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