Any topological space homeomorphic to the region in a plane between two concentric circles of different radius.
The ring of the sun not covered by the moon in an annular solar eclipse.
Structure in a fern that consists of differentially thick-walled cells on a sporangium that bend and distort as a result of drying.
A ring- or donut-shaped area or structure.
The region in a plane between two concentric circles of different radii.
The membranous remnants of a partial veil which leaves a ring on the stem of a mushroom.
The space contained between the centre well bore and any external tubing. Sometimes used for separated gas flow.
The set of points in a metric space of any number of dimensions lying within a given distance (the radius) of a given point.
Any sport or game involving a ball; its play, literally or figuratively.
A solid or hollow sphere, or roughly spherical mass.
A competitive event among young African-American and Latin American LGBTQ+ people in which prizes are awarded for drag and similar performances. See ball culture.
Nonsense.
A very enjoyable time.
The set of points in a topological space lying within some open set containing a given point.
An opportunity to launch the pinball into play.
The globe; the earthly sphere.
A pass; a kick of the football towards a teammate.
A pitch that falls outside of the strike zone.
The front of the bottom of the foot, just behind the toes.
Courage.
A large pill, a form in which medicine was given to horses; a bolus.
A formal dance.
A single delivery by the bowler, six of which make up an over.
In 3-dimensional Euclidean space, the volume bounded by a sphere.
A leather-covered cushion, fastened to a handle called a ballstock; formerly used by printers for inking the form, then superseded by the roller.
A roundish, protuberant portion of some part of the body.
An object that is the focus of many sports and games, in which it may be thrown, caught, kicked, bounced, rolled, chased, retrieved, hit with an instrument, spun, etc., usually roughly spherical but whose size, weight, bounciness, colour, etc. differ according to the game
A jacketed non-expanding bullet, typically of military origin.
One thousand US dollars.
A quantity of string, thread, etc., wound into a spherical shape.
To reject from a fraternity or sorority. (Short for blackball.)
To form or wind into a ball.
To gather balls which cling to the feet, as of damp snow or clay; to gather into balls.
To punish by affixing a ball and chain.
To have sexual intercourse with.
To heat in a furnace and form into balls for rolling.
To play basketball.
To be hip or cool.
An appeal by the crowd for holding the ball against a tackled player. This is heard almost any time an opposition player is tackled, without regard to whether the rules about "prior opportunity" to dispose of the ball are fulfilled.