Noun: blood brother blúd brú-dhu(r)
- A male sworn (usually by a ceremony involving the mingling of blood) to treat another as his brother
"The two friends became blood brothers in a solemn ritual"
- A male with the same parents as someone else
"my blood brother still lives with our parents";
- brother
Derived forms: blood brothers
Type of: adult male, ally, bozo [N. Amer, informal], cat [N. Amer, informal], chappie [Brit, informal], friend, geezer [Brit, informal], guy [informal], hombre [N. Amer, informal], male sibling, man, sod [informal]
Antonym: sis [informal]
Encyclopedia: Blood brother