A ring of metal wire looped almost twice about, as a keyring. / (electronics) Either of a pair of concentric metallic rings with slits on opposite sides, used in split-ring resonators.

A wedding ring.

An area at a racecourse in which bookmakers take bets from punters.

(slang) sovereign ring

A ring with a gold sovereign or similar coin as its primary decoration, with the obverse face as the visible detail.

Synonym of boxing ring

(mathematics) An algebraic structure similar to a ring but satisfying fewer axioms. They arise naturally from functions on groups.

A ringing noise made by a telephone-bell to announce an incoming call.

(photography) Synonym of ring light

(photography) A continuous circular strip of light around a camera lens (either directly on the rim or as a standalone item) for the purpose of evenly illuminating the subject.