deaconess vs imam

deaconess

noun
  • The nun in charge of the altar in a convent. 

  • A female servant in the early Christian church. 

  • One of an order of women in some Protestant churches who nurse the sick and tend the poor. 

  • A female deacon (Anglican). 

imam

noun
  • One who leads the salat prayers in a mosque. 

  • A Shi'ite Muslim leader descended from the prophet Muhammad and functioning as his spiritual successor. 

  • One of the Twelve imams, descendants of Muhammad from the seventh to ninth centuries CE who lived exemplary lives. 

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