\Half" blood`\
1. The relation between persons born of the same father or of
   the same mother, but not of both; as, a brother or sister
   of the half blood. See {Blood}, n., 2 and 4.

2. A person so related to another.

3. A person whose father and mother are of different races; a
   half-breed.

Note: In the 2d and 3d senses usually with a hyphen.