joist vs lintel

joist

noun
  • A piece of timber or steel laid horizontally, or nearly so, to which the planks of the floor, or the laths or furring strips of a ceiling, are nailed. 

verb
  • To fit or furnish with joists. 

lintel

noun
  • A horizontal structural beam spanning an opening, such as between the uprights of a door or a window, and which supports the wall above. 

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