radius
名词 radius:
the length of a line segment between the center and circumference of a circle or sphere
同义词:r
a straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)
a circular region whose area is indicated by the length of its radius
the outer and slightly shorter of the two bones of the human forearm
support consisting of a radial member of a wheel joining the hub to the rim
同义词:spoke, wheel spoke