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

Riding shotgun was Sumlin’s military blood brother, Sgt. 1st Class Jason Jarvis, a soldier on active-duty from Fort Bragg’s 18th Ordnance Company in North Carolina — Sumlin’s old unit.

From Seattle Times • Dec. 15, 2021

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

It opens with the lines: “My blood brother is an immigrant / A beautiful immigrant.”

From The Guardian • Oct. 14, 2020

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

My blood brother, Reginald, in whom I had so much confidence, for whom I had so much respect, the one who had introduced me to the Nation of Islam.

From "The Autobiography of Malcolm X" by Alex Malcolm X;Hailey