ra.di.us

radius的音标和读音：
DJ音标发音： [ˈreidi:əs]
KK音标发音： [ˈrediəs]

radius的词性：
n.（名词）

1. Abbr. R, r, radMathematics
缩写 R， r， rad【数学】

2. A line segment that joins the center of a circle with any point on its circumference.
圆半径：将圆心与圆周上任一连接起来的线段

3. A line segment that joins the center of a sphere with any point on its surface.
球半径：将心与球面上任一点起来的线段

4. A line segment that joins the center of a regular polygon with any of its vertices.
将正多边形的中心与它的一任一顶点起的来的线段

5. The length of any such line segment.
半距离：这种线段的长度

6. A circular area measured by a given radius:
半径范围：以某一半径所计的圆形地区：

every family within a radius of 25 miles of the city center.
住在离城中心半径25英里的范围内的家庭

7. A bounded range of effective activity or influence:
活动半径：有效活动或影响的边界范围：

the operating radius of a helicopter.
直升飞机的作战半径

8. A radial part or structure, such as a mechanically pivoted arm or the spoke of a wheel.
辐射部分：辐射形的部件或结构，如机械上有轴的臂或车轮的辐条

9. Anatomy
【解剖学】

10. A long, prismatic, slightly curved bone, the shorter and thicker of the two forearm bones, located on the lateral side of the ulna.
桡骨：一种长的、棱柱状、微弯的内头，两根前臂骨中较短较粗的一根，位于尺骨的后侧

11. A similar bone in many vertebrates.
桡骨：许多脊椎动物具有的类似的骨头

radius的词源：

12. Latin [ray]
拉丁语 [射线]