sphere

球、球体

ボールのように、どの方向から見ても丸い形や物。

やさしい英語で： A completely round shape or object, like a ball.

• The lamp is shaped like a sphere.
• She held a small glass sphere.
• The Earth is almost a perfect sphere.

類義語： ball, globe

よく使う表現： glass sphere, solid sphere, perfect sphere

領域、分野

人が活動したり、責任を持ったり、影響を及ぼしたりする生活や仕事の分野。

やさしい英語で： An area of life or work in which someone acts, has responsibility, or has influence.

• Her work belongs to the political sphere.
• The matter falls outside my sphere of responsibility.
• His influence extends into several different spheres of public life.

使い方： sphere of something (The company expanded its sphere of influence.)

類義語： domain, field, area

よく使う表現： sphere of influence, public sphere, political sphere

球面

一つの中心点から同じ距離にある、すべての点でできる面。

やさしい英語で： A surface consisting of all points at the same distance from a central point.

• Every point on a sphere is equally distant from its centre.
• Draw a sphere with a radius of two units.
• The equation describes a sphere in three-dimensional space.

よく使う表現： unit sphere, sphere surface, sphere of radius