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

Inflected Forms

noun

• radius vectors
  plural
• radii vectores
  plural

Etymology

Origin of radius vector

First recorded in 1745–55

Example Sentences

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

From Textbooks • Mar. 30, 2016

This result is in perfect harmony with Kepler's Second Law, which states that equal areas are described by the radius vector in equal times.

From Aether and Gravitation by Hooper, William George

The problem of constructing successive radii vectores, the angles of which are measured off from the radius vector of the body at the original given position, is then a geometric one, known as Kepler’s problem.

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

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

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