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blood brother

noun

Definition of blood brother

1 :a brother by birth
2 :one of two men pledged to mutual loyalty by a ceremonial use of each other's blood
—

blood brotherhood

noun

See blood brother defined for English-language learners

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Examples of blood brother in a Sentence

  1. He would never betray me—he's my blood brother.

First Known Use of blood brother

1799

BLOOD BROTHER Defined for English Language Learners

blood brother

noun

Definition of blood brother for English Language Learners

  • : a man or boy who has promised to be loyal to another man or boy usually in a ceremony in which they mix their blood

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Examples: blood brother in a Sentence