n.

1. 半徑；半徑距離；半徑範圍[C][the S][（+of）]
   There are three lakes within a radius of five miles.

   周圍五英里之內有三個湖泊。

2. 周圍，範圍[the S][（+of）]
   within the radius of one's experience

   在個人經驗範圍之內

3. 輻射狀部分；（車輪的）輻條[C]
4. 【解】橈骨[C]
5. 【動】徑骨[C]
6. 【昆】徑脈[C]

n.

1. a straight line from the centre to the circumference of a circle or sphere.
   ▸a radial line from the focus to any point of a curve.
2. a specified distance from a centre in all directions:
   there are plenty of pubs within a two-mile radius.
3. Anatomy  & Zoology  a bone of the forearm or forelimb, in humans the thicker and shorter of two.
4. Zoology  a radially symmetric feature in an echinoderm or coelenterate, e.g. an arm of a starfish.
5. Entomology  a main vein in an insect's wing.

v.