open marriage

American  

noun

1. a marriage in which the partners agree that each is free to have sexual relationships with other partners.

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open marriage British  

noun

1. a marriage in which the partners are free to pursue their own social and sexual lives

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Etymology

Origin of open marriage

First recorded in 1970–75

Example Sentences

Come for the haunting bangers about her open marriage to ‘Stranger Things’ star David Harbour and their Architectural Digest video; stay for Dallas Major and Madeline.”

From Los Angeles Times • Dec. 17, 2025

It's entirely possible that nothing, not even an open marriage, could have saved Love and Joe's ultimately doomed relationship.

From Salon • Oct. 25, 2021

I know you’re big fans of open marriage, but I can’t picture not getting overly attached to someone else, and I don’t want that either.

From Slate • Jan. 14, 2020

Mrs. Knatchbull and her sister were raised by a governess and did not consider themselves close to their mother, who was absent for much of their upbringing and had a notoriously open marriage.

From Washington Post • Jun. 17, 2017

Abélard would perhaps have consented to an open marriage had Héloïse been willing; but with a strange perversity she refused.

From Beacon Lights of History, Volume 07 Great Women by Lord, John