Blood brother is a phrase with a literal and figurative meaning, which means it is sometimes used as an idiom. We will examine the definition of the expression blood brother, where it may have come from and some examples of its use in sentences.
The first, literal definition of the term blood brother is a male sibling who is genetically related to another sibling, or a male sibling who is related to another sibling by birth. Most often, the term blood brother is used as an idiom to mean a male who one is emotionally close to, but is not related to by genetics or by birth. This emotional relationship entails an oath of loyalty and devotion, whether formal or informal. The term refers to ceremonies performed over many cultures in which two men swear allegiance and fidelity to each other as brothers, and seal the promise by making cuts in each of their bodies in order to mingle their blood. This practice goes back at least as far as the fourth century B.C. in Scythia, where men united as brothers by dripping their blood into wine, and then drinking it. Though rituals in which men became blood brothers were common in Asia, Europe and Africa, it is the Native American ritual that inspired legions of boys living in the United States in the 1950s and 1960s to perform their own rituals making themselves blood brothers. Today, the act of becoming blood brothers through physically mingling blood is greatly discouraged, because of the scourge of AIDS, hepatitis, and other blood-borne illnesses. The expression blood brother has been in use since the late 1700s. Note that the plural of blood brother is blood brothers.
Examples
Their relation occurred as a result of Reverend Amituana’i Anoa’i, Reigns’ grandfather, declaring Peter Maivia, The Rock’s grandfather, as his blood brother – something that holds deep meaning within Samoan culture. (The Sunday Express)
Several people have since recorded statements with the police probing the shooting, among them Governor Ali Korane and his blood brother. (Hivisasa)
The quintet from the land of Brexit revs up a stirring homage to its “blood brother,” a Ukrainian immigrant. (The Chicago Tribune)
R Madhavan was the happiest when he joined Twitter and his tweet calling Paresh ‘more than a blood brother’, his ‘inspiration and idol’, and ‘go-to-man’ for all his issues was something not many were aware of. (The Deccan Chronicle)
Yakuza 4 splits the action between four characters: series hero Kazuma Kiryu, loan shark Shun Akiyama, dirty cop Masayoshi Tanimura and Taiga Saejima, former blood brother of the one and only Goro Majima. (Newsweek)