万能钥匙

[ noun ]
a passkey with much of the bit filed away so that it can open different locks
<noun.artifact>

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.

{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} (Zo["o]l.), a small crustacean of the genus
{Caprella}. See Illust. under {L[ae]modipoda}.