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v. Simple past tense and past participle of groin.

adj. Built with groins.

In architecture, having groins; showing the curved lines resulting from the intersection of two semicylinders or arches. See cut under groin.

"The room in which Queen Bimbane received me was a superb apartment, magnificently decorated with elaborately carved columns supporting a kind of groined roof, the walls being draped with splendid tapestry worked on silk in gold thread, and hung with several enormous mirrors of polished silver in massive gold frames -- brackets supporting clusters of lamps on either side of each."

groined ceiling   

groin   

coined    conjoined    enjoined    joined    purloined