The Collaborative International Dictionary of English v.0.48:

Skeleton \Skel"e*ton\, a.
   Consisting of, or resembling, a skeleton; consisting merely
   of the framework or outlines; having only certain leading
   features of anything; as, a skeleton sermon; a skeleton
   crystal.
   [1913 Webster]

   Skeleton bill, a bill or draft made out in blank as to the
      amount or payee, but signed by the acceptor. [Eng.]

   Skeleton key, a key with nearly the whole substance of the
      web filed away, to adapt it to avoid the wards of a lock;
      a master key; -- used for opening locks to which it has
      not been especially fitted.

   Skeleton leaf, a leaf from which the pulpy part has been
      removed by chemical means, the fibrous part alone
      remaining.

   Skeleton proof, a proof of a print or engraving, with the
      inscription outlined in hair strokes only, such proofs
      being taken before the engraving is finished.

   Skeleton regiment, a regiment which has its complement of
      officers, but in which there are few enlisted men.

   Skeleton shrimp (Zool.), a small crustacean of the genus
      Caprella. See Illust. under Laemodipoda.
      [1913 Webster]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

SKELETON BILL, com. law. A blank paper, properly stamped, in those countries
where stamps are required, with the name of a person signed at the bottom.
     2. In such case the person signing the paper will be held as the drawer
or acceptor, as it may be, of any bill which shall afterwards be written
above his name to the sum of which the stamp is applicable. 1 Bell's Com.
390, 5th ed.