godmother vs maid of honor

godmother

noun
  • A woman present at the christening of a baby who promises to help raise the child in a Christian manner; a female godparent who sponsors the baptism of a child. 

verb
  • To act as godmother to. 

maid of honor

noun
  • The primary woman who attends the bride at a wedding ceremony. 

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