ring

(physical) A solid object in the shape of a circle.

(physical) A group of objects arranged in a circle.

A piece of food in the shape of a ring.

"onion rings"

A place where some sports or exhibitions take place; notably a circular or comparable arena, such as a boxing ring or a circus ring; hence the field of a political contest.

To enclose or surround.

"The inner city was ringed with dingy industrial areas."

To make an incision around; to girdle.

"They ringed the trees to make the clearing easier next year."

To attach a ring to, especially for identification.

"We managed to ring 22 birds this morning."

To surround or fit with a ring, or as if with a ring.

"to ring a pig’s snout"

The resonant sound of a bell, or a sound resembling it.

"The church bell's ring could be heard the length of the valley."

A pleasant or correct sound.

"The name has a nice ring to it."

A sound or appearance that is characteristic of something.

"Her statements in court had a ring of falsehood."

A telephone call.

"I’ll give you a ring when the plane lands."

Of a bell, etc., to produce a resonant sound.

"The bells were ringing in the town."

To make (a bell, etc.) produce a resonant sound.

"The deliveryman rang the doorbell to drop off a parcel."

To produce (a sound) by ringing.

"They rang a Christmas carol on their handbells."

To produce the sound of a bell or a similar sound.

"Whose mobile phone is ringing?"

An algebraic structure which consists of a set with two binary operations: an additive operation and a multiplicative operation, such that the set is an abelian group under the additive operation, a monoid under the multiplicative operation, and such that the multiplicative operation is distributive with respect to the additive operation.

"The set of integers, \mathbb{Z}, is the prototypical ring."

An algebraic structure as above, but only required to be a semigroup under the multiplicative operation, that is, there need not be a multiplicative identity element.

"The definition of ring without unity allows, for instance, the set 2\mathbb{Z} of even integers to be a ring."