chittim vs shittimwood

chittim

noun
  • The false buckthorn, Bumelia Lanuginosa. 

  • The cascara, Rhamnus purshiana. 

  • The yellow cottonwood , Populus deltoides. 

  • A type of wood mentioned in the Bible, from which the Ark of the Covenant was constructed. 

  • A Nigerian currency. 

shittimwood

noun
  • The wood of the shittim. 

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