radius vector

American  

noun

radii vectores, plural radius vectors plural

1. Mathematics. the length of the line segment joining a fixed point or origin to a given point.

2. Astronomy.

   1. the straight line joining two bodies in relative orbital motion, as the line from the sun to a planet at any point in its orbit.

   2. the distance between two such bodies at any point in the orbit.

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radius vector British  

noun

1. maths a line joining a point in space to the origin of polar or spherical coordinates

2. astronomy an imaginary line joining a satellite to the planet or star around which it is orbiting

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radius vector Scientific  

1. A line segment that joins the origin and a variable point in a system of polar or spherical coordinates.

2. The imaginary straight line that connects the center of the Sun or another body with the center of a planet, comet, or other body that orbits it.

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Other Word Forms

Noun Inflected Forms

• radii vectores
  plural
• radius vectors
  plural

Etymology

Origin of radius vector

First recorded in 1745–55

Example Sentences

See Examples For:

radius vector

Note that the torque vector is orthogonal to both the force vector and the radius vector.

From Textbooks ● Mar. 30, 2016

Hodograph, hod′o-graf, n. a curve the radius vector of which represents in direction and magnitude the velocity of a moving particle—a term suggested by Sir W. R. Hamilton.

From Chambers's Twentieth Century Dictionary (part 2 of 4: E-M) by Various

Of the three co-ordinates, the radius vector does not admit of direct measurement, and must be inferred by a combination of indirect measurements and physical theories.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 7 "Arundel, Thomas" to "Athens" by Various

So Kepler formulated his second great law of planetary motion very simply: the radius vector of any planet describes, or sweeps over, equal areas in equal times.

From Astronomy: The Science of the Heavenly Bodies by Todd, David Peck

In a curve referred to polar co”rdinates, any point for which the radius vector is a maximum or minimum.

From Webster's Unabridged Dictionary by Webster, Noah