blood brother

American  

noun

1. a person's brother by birth.

2. a male person bound to another by ties of great friendship.

3. something usually associated with or thought to exist inseparably from another thing, quality, circumstance, etc..

   Humility is often the blood brother of patience.

4. a male established in a close relationship with another male through the performance of a specific ritual, as the commingling of blood.

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blood brother British  

noun

1. a brother by birth

2. a man or boy who has sworn to treat another as his brother, often in a ceremony in which their blood is mingled

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Other Word Forms

Derived Forms

• blood brotherhood
  noun

Etymology

Origin of blood brother

Middle English word dating back to 1350–1400

Example Sentences

“Gangsta Boo was like a sister to me and told the world about me the way my blood brother did,” Drumma Boy said in a statement.

From Seattle Times • Jan. 2, 2023

It’s also an origin story for Tomisaburo, or Storm Shadow — the prominent hero/villain and blood brother to Snake Eyes.

From Los Angeles Times • Jul. 22, 2021

He feels he must go to save Bon, his blood brother, from dying in what he’s sure will be a suicide mission.

From New York Times • Apr. 2, 2015

Director Amat Escalante – a more explicitly political blood brother to Mexico's current king of neo-realist weirdness, Carlos Reygadas – has shot a damning indictment of contemporary Mexico, capturing its institutionalised corruption, its endemic cruelty.

From The Guardian • May 16, 2013

Kvasir said, “It is true that Loki is a blood brother to the gods, and we cannot kill him. But we are bound by no such oaths to you, his sons.”

From "Norse Mythology" by Neil Gaiman