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. [ 1913 Webster ]
2. A person so related to another. [ 1913 Webster ]
3. A person whose father and mother are of different races; a half-breed. [ 1913 Webster ]
☞ In the 2d and 3d senses usually with a hyphen. [ 1913 Webster ]