- a straight line joining the origin of a vector, located at the intersection of two coordinates, to a given point lying in the same plane
- a vector whose point of origin is fixed and whose terminal point ranges over a given curve or surface, as a straight line connecting the sun with the earth at any point of the earth's orbit
- Mathematics a. A line segment that joins the origin and a variable point in a system of polar or spherical coordinates.b. The length of such a line segment.
- Astronomy A straight line connecting the center of mass of a satellite, such as a planet, moon, or comet, to the center of mass of the body it orbits, such as the sun or Earth. Also called position vector.
(plural radius vectors)
- (mathematics) A straight line (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.
- (astronomy) 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.
Part or all of this entry has been imported from the 1913 edition of Webster's Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.