black man vs ebony

black man

noun
  • Used other than figuratively or idiomatically: see black, man. 

  • A male adult member of an ethnic group having dark pigmentation of the skin, typically of sub-Saharan African descent; or the appearance thereof. 

ebony

noun
  • A deep, dark black colour. 

  • A black key on a piano or other keyboard instrument. 

  • A tree that yields such wood. 

  • A hard, dense, deep black wood from various subtropical and tropical trees, especially of the genus Diospyros. 

adj
  • Made of ebony wood. 

  • Dark-skinned; black; especially in reference to African-Americans. 

  • A deep, dark black colour. 

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