delegacy vs delegation

delegacy

noun
  • A collection of delegates. 

  • The position or state of being a delegate. 

delegation

noun
  • A group of delegates used to discuss issues with an opponent. 

  • An act of delegating. 

  • The act whereby or constellation in which the performance of an obligation (owed to an obligee, presuming its validity; irrespective of the obligation as the target of the delegation, rarely called delegatary) is assigned by its debtor (delegator, obligor) to and towards another party (delegatee, delegate) 

  • A method-dispatching technique describing the lookup and inheritance rules for self-referential calls. 

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