groomsman vs usher

groomsman

noun
  • A man who serves as one of a number of attendants to a bridegroom at a wedding, one of whom is the best man. 

usher

noun
  • A male escort at a wedding. 

  • A doorkeeper in a courtroom. 

  • A person, in a church, cinema etc., who escorts people to their seats. 

verb
  • To lead or guide somewhere. 

  • To precede; to act as a forerunner or herald. 

  • To accompany or escort (someone). 

  • To guide people to their seats. 

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