carrel vs exedra

carrel

noun
  • Hence, a partially partitioned space for studying or reading, often in a library. 

  • A small closet or enclosure built against a window on the inner side, to sit in for study. 

  • A square-headed arrow; a quarrel. 

exedra

noun
  • A semicircular recess, with stone benches, used as a place for discussion. 

  • A curved bench with a high back. 

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