bast vs casing

bast

noun
  • Fibre made from the phloem of certain plants and used for matting and cord. 

casing

noun
  • The decorative trim around a door or window. 

  • That which encloses or encases. 

  • A metal pipe used to line the borehole of a well. 

  • The state of letter case across a whole phrase or whole lines of text; the collective state/arrangement of uppercase and lowercase letters. 

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