长幅圆滚线

Curtate \Cur"tate\ (k?r"t?t), a. [L. curtatus, p. p. of curtare
to shorten, fr. curtus. See {Curt}.] (Astron.)
Shortened or reduced; -- said of the distance of a planet
from the sun or earth, as measured in the plane of the
ecliptic, or the distance from the sun or earth to that point
where a perpendicular, let fall from the planet upon the
plane of the ecliptic, meets the ecliptic.

{Curtate cycloid}. (Math.) See {Cycloid}.