beshow vs black cod

beshow

noun
  • A large food fish (Anoplopoma fimbria) of the north Pacific coast; the candlefish or sablefish. 

black cod

noun
  • Synonym of sablefish (Anoplopoma fimbria); (the sablefish is not a species of codfish; but is referred to as cod informally) 

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