conventicle vs seminar

conventicle

noun
  • The place where such a meeting is held. 

  • A secret, unauthorized or illegal religious meeting. 

  • A Quaker meetinghouse. 

verb
  • To hold a secret, unauthorized or illegal religious meeting. 

seminar

noun
  • A meeting held for the exchange of useful information by members of a common business community. 

  • A class held for advanced studies in which students meet regularly to discuss original research, under the guidance of a professor. 

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