Chapter Q to Quadrilateral of Q by Webster's Dictionary (1913 Edition)

2. A quadrate; a square. Milton.

3. (Integral Calculus) The integral used in obtaining the area bounded by a curve; hence, the definite integral of the product of any function of one variable into the differential of that variable.

4. (Astron.) The position of one heavenly body in respect to another when distant from it 90°, or a quarter of a circle, as the moon when at an equal distance from the points of conjunction and opposition.

Quadrature of the moon (Astron.), the position of the moon when one half of the disk is illuminated. — Quadrature of an orbit (Astron.), a point in an orbit which is at either extremity of the latus rectum drawn through the empty focus of the orbit.

Quadrel
(Quad"rel) n. [It. quadrello, LL. quadrellus, fr. L. quadrus square. See Quadrate, and cf. Quarrel an arrow.]

1. A square piece of turf or peat. [Prov. Eng.]

2. A square brick, tile, or the like.

Quadrennial
(Quad*ren"ni*al) a. [L. quadriennium a space of four years; quattuor four + annus year; cf. L. quadriennis. See Quadrate, and Annual.]

1. Comprising four years; as, a quadrennial period.

2. Occurring once in four years, or at the end of every four years; as, quadrennial games.

Quadrennially
(Quad*ren"ni*al*ly), adv. Once in four years.

Quadrennium
(||Quad*ren"ni*um) n. [NL. See Quadrennial.] A space or period of four years.

Quadri-
(Quad"ri-) [L., from quattuor four. See Four.] A combining form meaning four, four times, fourfold; as, quadricapsular, having four capsules.

Quadribasic
(Quad`ri*ba"sic) a. [Quadri- + basic.] (Chem.) Same as Tetrabasic.

Quadrible
(Quad"ri*ble) a. Quadrable. [R.]

Quadric
(Quad"ric) a. (Math.) Of or pertaining to the second degree.

Quadric
(Quad"ric), n. (a) (Alg.) A quantic of the second degree. See Quantic. (b) (Geom.) A surface whose equation in three variables is of the second degree. Spheres, spheroids, ellipsoids, paraboloids, hyperboloids, also cones and cylinders with circular bases, are quadrics.

Quadricapsular
(Quad`ri*cap"su*lar) a. [Quadri- + capsular.] (Bot.) Having four capsules.

Quadriceps
(||Quad"ri*ceps) n. [NL., fr. L. qyattuor four + caput head.] (Anat.) The great extensor muscle of the knee, divided above into four parts which unite in a single tendon at the knee.

Quadricipital
(Quad`ri*cip"i*tal) n. (Anat.) Of or pertaining to the quadriceps.

Quadricorn
(Quad"ri*corn) n. [See Quadricornous.] (Zoöl.) Any quadricornous animal.

Quadricornous
(Quad`ri*cor"nous) a. [Quadri- + L. cornu horn: cf. F. quadricorne.] (Zoöl.) Having four horns, or hornlike organs; as, a quadricornous beetle.

Quadricostate
(Quad`ri*cos"tate) a. [Quadri- + costate.] Having four ribs.