Webster’s Revised Unabridged Dictionary · 1913
Lune
Lune (lūn), n. [L. luna moon: cf. F. lune. See Luna.] 1. Anything in the shape of a half moon. [R.]
2. (Geom.) A figure in the form of a crescent, bounded by two intersecting arcs of circles.
3. A fit of lunacy or madness; a period of frenzy; a crazy or unreasonable freak. [Obs.]
These dangerous, unsafe lunes i' the king. Shak.