SG Heritage Dictionary

Radius [Noun] Webster's Dictionary 1828

1. In geometry, a right line drawn or extending from the center of a circle to the periphery, and hence the semidiameter of the circle. In trigonometry, the radius is the whole sine, or sine of 90 degrees.

2. In anatomy, the exterior bone of the fore arm, descending along with the ulna from the elbow to the wrist.

3. In botany, a ray; the outer part or circumference of a compound radiate flower, or radiated discous flower.

Radius [Noun] Webster's Dictionary 1913

1. A right line drawn or extending from the center of a circle to the periphery; the semidiameter of a circle or sphere.

2. The preaxial bone of the forearm, or brachium, corresponding to the tibia of the hind limb. See Illust. of Artiodactyla.

3. A ray, or outer floret, of the capitulum of such plants as the sunflower and the daisy. See Ray, 2.

4. The barbs of a perfect feather.

5. Radiating organs, or color-markings, of the radiates.

6. The movable limb of a sextant or other angular instrument.

Radius vector Webster's Dictionary 1913

A straight line (or the length of such line) connecting any point, as of a curve, with a fixed point, or pole, round which the straight line turns, and to which it serves to refer the successive points of a curve, in a system of polar coordinates. See Coordinate, n.

Radius vector [Noun] Webster's Dictionary 1913

An ideal straight line joining the center of an attracting body with that of a body describing an orbit around it, as a line joining the sun and a planet or comet, or a planet and its satellite.

Radiuses [Plural] Webster's Dictionary 1913

of Radius