loof vs metacarpus

loof

noun
  • The palm of the hand. 

  • The spongy fibers of the fruit of a cucurbitaceous plant (Luffa aegyptiaca). 

  • The after part of the bow of a ship where the sides begin to curve. 

  • The hand, especially, the hand outspread and upturned. 

metacarpus

noun
  • The five bones that form the intermediate part of the hand between the fingers and the wrist. 

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