shotgun marriage

n.
A marriage that is forced or necessitated because of pregnancy. Also called shotgun wedding.

An agreement or compromise made through necessity, as in Since neither side won a majority, the coalition government was obviously a shotgun wedding. This expression alludes to a marriage precipitated by a woman's pregnancy, causing her father to point a literal or figurative gun at the responsible man's head. Its figurative use dates from the mid-1900s.

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