- 1
A semicircle is half a circle: a round line, or a round slice, cut straight through the centre. You meet it in maths, in buildings (a round arch), and in ordinary life — a class sitting in a semicircle on the floor so everyone can see. People use it a little loosely, too: a “semicircle of chairs” is often just a curved row, not a perfect half-disc, and nobody minds. There is a verb, to semicircle, meaning to move or stand in that shape, but the noun is the one you will actually meet. Draw a diameter and keep one side of the curve: that is the whole idea.
半圓
組成semi- (half) + circle
同家族的字
- circlethe full round shape this is half of
- circularthe adjective for “like a circle”
- semicircularthe adjective for this shape
原始詞典資料4 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
semicirclenoun
- 1
A half of a circle.
- 2
A surveyor's instrument for measuring angles; a graphometer.
- 3
ball-gamesgameshobbiesAn arc whose center is the penalty spot, extending from the top of the penalty area.
semicircleverb
- 1
To travel or move around in a semicircle.
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。