名詞 epicycle:

1. a circle that rolls around (inside or outside) another circle; generates an epicycloid or hypocycloid

ep.i.cy.cle

n.（名詞）
In Ptolemaic cosmology, a small circle, the center of which moves on the circumference of a larger circle at whose center is Earth and the circumference of which describes the orbit of one of the planets around Earth.
本輪：在托勒密宇宙論中的一個(gè)小的圓周，其中心在以地球?yàn)橹行牡囊粋€(gè)更大的圓周上運(yùn)動(dòng)，其軌跡為環(huán)繞地球運(yùn)行的行星的軌道
Mathematics A circle whose circumference rolls along the circumference of a fixed circle, thereby generating an epicycloid or a hypocycloid.
【數(shù)學(xué)】 周轉(zhuǎn)圓：一個(gè)圍繞著另一個(gè)固定圓周長(zhǎng)滾動(dòng)的圓，從而產(chǎn)生圓外旋輪線或圓內(nèi)旋輪線，即外擺線或內(nèi)擺線

來(lái)源：
Middle English epicicle
中古英語(yǔ) epicicle
from Late Latin epicyclus
源自 后期拉丁語(yǔ) epicyclus
from Greek epikuklos
源自 希臘語(yǔ) epikuklos
epi- [epi-]
epi- [前綴，表.在…之間.]
kuklos [circle] * see k wel-
kuklos [圓周] *參見(jiàn) k wel-

【引伸】
ep.icy.clic