introducer vs sire

introducer

noun
  • Someone or something that introduces. 

sire

verb
  • to father; to beget. 

noun
  • A male animal that has fathered a particular offspring (especially used of domestic animals and/or in biological research). 

  • A lord, master, or other person in authority, most commonly used vocatively: formerly in speaking to elders and superiors, later only when addressing a sovereign. 

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