passed pawn vs passer

passed pawn

noun
  • A pawn that has passed beyond enemy pawns on its own or adjacent files, and that hence has a clear run to the first or eighth rank. 

passer

noun
  • A passed pawn. 

  • One who is able to "pass", or be accepted as a member of a race, sex or other group to which society would not otherwise regard them as belonging. 

  • One who passes something along; a distributor. 

  • Someone who passes, someone who makes a pass. 

  • One who succeeds in passing a test, etc. 

  • A football player who makes a forward pass, who may be (but not limited to) the quarterback. 

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