(algebra, ring theory) For a given ring R and ideal I contained in R, another ring, denoted R / I, whose elements are the cosets of I in R.

(algebra, ring theory) Any nonzero ring R such that for any two (two-sided) ideals P and Q in R, the product PQ = 0 (the zero ideal) if and only if P = 0 or Q = 0.

(nautical) A ring of metal attached to a dock to which boats may be attached by a rope.

plural of ring leader

A form of body art wherein a piercing is placed in a cauterized puncture of the umbilicus.

A finger ring with a short inscription, once popular as lovers' tokens in England.

A closed loop of lasers with two beams of light travelling in opposite directions.

(algebra, ring theory) A ring which is either: (a) a commutative ring in which every ideal is finitely generated, or (b) a noncommutative ring that is both left-Noetherian (every left ideal is finitely generated) and right-Noetherian (every right ideal is finitely generated).

(algebra, ring theory) A ring whose multiplicative operation is commutative.

Any of various satyrine butterflies of the genus Ypthima, having circular markings on the wings.