1A line of variable length drawn from a fixed origin to a curve.
〔数〕径向量，位置向量
Example sentencesExamples
In fact, from the point P which is at distance d from the origin measured along a radius vector, the distance from P to the pole is d sec b.
The cylindrical coordinate system, (R, Z), was introduced for this boundary, where Z is the axis perpendicular to the plane passing through the boundary, and R is the two-dimensional radius vector in this plane.
When Archimedes defines a spiral, he gives fundamental properties connecting the length of the radius vector with the angles through which it has revolved.
Three days later he wrote to Le Verrier asking the same question about the radius vector as he had asked Adams.
1.1Astronomy A line of variable length joining a satellite or other celestial object to its primary.
〔天文〕矢径，向径
Example sentencesExamples
In the second law, Kepler used the idea of radius vector, and stated that the radius vector from the sun to a planet sweeps out equal areas in equal intervals of time.
The radius vector is shortest when the planet is at perihelion and longest at aphelion.
The radius vector from the sun to a planet sweeps over equal areas in equal times.
Definition of radius vector in US English:
radius vector
noun
Mathematics
1A line of variable length drawn from a fixed origin to a curve.
〔数〕径向量，位置向量
Example sentencesExamples
When Archimedes defines a spiral, he gives fundamental properties connecting the length of the radius vector with the angles through which it has revolved.
Three days later he wrote to Le Verrier asking the same question about the radius vector as he had asked Adams.
The cylindrical coordinate system, (R, Z), was introduced for this boundary, where Z is the axis perpendicular to the plane passing through the boundary, and R is the two-dimensional radius vector in this plane.
In fact, from the point P which is at distance d from the origin measured along a radius vector, the distance from P to the pole is d sec b.
1.1Astronomy A line joining a satellite or other celestial object to its primary.
〔天文〕矢径，向径
Example sentencesExamples
The radius vector is shortest when the planet is at perihelion and longest at aphelion.
The radius vector from the sun to a planet sweeps over equal areas in equal times.
In the second law, Kepler used the idea of radius vector, and stated that the radius vector from the sun to a planet sweeps out equal areas in equal intervals of time.