: the relation between persons having only one parent in common also : a person so related to another. More from Merriam-Webster on half-blood.

What is the official term for Half Blood?

Other definitions for half blood (2 of 2)

a person who has only one parent in common with another person, as a half sister or half brother.

Where did the word half blood come from?

"person of mixed race," 1826; see half + blood (n.). As an adjective, "born of one parent the same and one different," from 1550s.