cycloid
n. 摆线,圆滚线
adj. 圆形的;情绪起伏不定的
例句
The cycloid has an isochronal pendulum.
摆线具有严格的等时摆。
Ok, so that's what the cycloid looks like.
这就是摆线了。
Let's take, so, it's a famous curve called a cycloid.
来看看一条著名的曲线——摆线。