What is "elliptic chuck"

Elliptic \El*lip"tic\, Elliptical \El*lip"tic*al\, a. [Gr. ?: cf. F. elliptique. See Ellipsis.]

1. Of or pertaining to an ellipse; having the form of an ellipse; oblong, with rounded ends.

   The planets move in elliptic orbits.
   --Cheyne.

   The billiard sharp who any one catches, His doom's extremely hard He's made to dwell In a dungeon cell On a spot that's always barred. And there he plays extravagant matches In fitless finger-stalls On a cloth untrue With a twisted cue And elliptical billiard balls!
   --Gilbert and Sullivan (The Mikado: The More Humane Mikado Song)

2. Having a part omitted; as, an elliptical phrase.

3. leaving out information essential to comprehension; so concise as to be difficult to understand; obscure or ambiguous; -- of speech or writing; as, an elliptical comment.

   Elliptic chuck. See under Chuck.

   Elliptic compasses, an instrument arranged for drawing ellipses.

   Elliptic function. (Math.) See Function.

   Elliptic integral. (Math.) See Integral.

   Elliptic polarization. See under Polarization.

Chuck \Chuck\, n.

1. A slight blow or pat under the chin.

2. A short throw; a toss.

3. (Mach.) A contrivance or machine fixed to the mandrel of a lathe, for holding a tool or the material to be operated upon.

   Chuck farthing, a play in which a farthing is pitched into a hole; pitch farthing.

   Chuck hole, a deep hole in a wagon rut.

   Elliptic chuck, a chuck having a slider and an eccentric circle, which, as the work turns round, give it a sliding motion across the center which generates an ellipse.
   --Knight.