Source : Webster's Revised Unabridged Dictionary (1913)

Lune \Lune\, 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.