blood oath


: an oath taken by two or more people in which they ceremonially use or exchange each other's blood
broadly : a very serious or solemn oath
… she'd have to sign a blood oath promising that no matter what happened she'd never leave once that child was born … Ron Harris, Elle, March 1993
Back when we were 17, we all took a blood oath to record three albums of 30-minute punk rock, and nobody would get to leave until we'd done just that. Pelle Almqvist, Spin, November 2007

Word History

First Known Use

1856, in the meaning defined above

Time Traveler
The first known use of blood oath was in 1856

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Dictionary Entries Near blood oath

Cite this Entry

“Blood oath.” Dictionary, Merriam-Webster, Accessed 16 Apr. 2024.

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