lector vs octavo

lector

noun
  • A lay person who reads aloud certain religious texts in a church service. 

  • A public lecturer or reader at some universities. 

  • A person doing voice-over translation of foreign films, especially in Eastern European countries. 

  • A person who reads aloud to workers to entertain them, appointed by a trade union. 

verb
  • To do a voice-over translation of a film. 

octavo

noun
  • A book of octavo pages. 

  • A sheet of paper 7 to 10 inches (= 17.78 to 25.4 cm) high and 4.5 to 6 inches (= 11.43 to 15.24 cm) wide, the size varying with the large original sheet used to create it. It is made by folding the original sheet three times to produce eight leaves. 

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