present participle of square the circle

(philately) A cancellation mark consisting of an outer ring of concentric circles, cropped into a square shape.

(sports, boxing, wrestling, professional wrestling) The boxing or wrestling ring.

(geometry) A circle of radius 1. / (trigonometry, the unit circle) The circle of radius 1 with centre at the origin, used in defining trigonometric functions.

(soccer) The circle in the centre of the pitch which, at kick-off, the defending team may not enter until the attacking side has touched the ball.

(baseball) The circle drawn or painted on the field where the next batter to hit waits.

The third largest city in Ohio, United States and the county seat of Hamilton County. / A city in Appanoose County, Iowa. / An unincorporated community in Washington County, Arkansas.

(bowling) A 7–9 or 8–10 split (result of a first throw).

(cryptography) A method of encryption by which units of plaintext are substituted with ciphertext according to a regular system; the "units" may be single letters (the most common), pairs of letters, triplets of letters, mixtures of the above, and so forth. The receiver deciphers the text by performing an inverse substitution.

(automotive, of a road vehicle) The circular path formed by the wheel furthest from the centre of the turn when turning to the maximum extent.