The Collaborative International Dictionary of English v.0.48:

Chancery \Chan"cer*y\, n. [F. chancellerie, LL. cancellaria,
   from L. cancellarius. See Chancellor, and cf.
   Chancellery.]
   1. In England, formerly, the highest court of judicature next
      to the Parliament, exercising jurisdiction at law, but
      chiefly in equity; but under the jurisdiction act of 1873
      it became the chancery division of the High Court of
      Justice, and now exercises jurisdiction only in equity.
      [1913 Webster]

   2. In the Unites States, a court of equity; equity;
      proceeding in equity.
      [1913 Webster]

   Note: A court of chancery, so far as it is a court of equity,
         in the English and American sense, may be generally, if
         not precisely, described as one having jurisdiction in
         cases of rights, recognized and protected by the
         municipal jurisprudence, where a plain, adequate, and
         complete remedy can not be had in the courts of common
         law. In some of the American States, jurisdiction at
         law and in equity centers in the same tribunal. The
         courts of the United States also have jurisdiction both
         at law and in equity, and in all such cases they
         exercise their jurisdiction, as courts of law, or as
         courts of equity, as the subject of adjudication may
         require. In others of the American States, the courts
         that administer equity are distinct tribunals, having
         their appropriate judicial officers, and it is to the
         latter that the appellation courts of chancery is
         usually applied; but, in American law, the terms equity
         and court of equity are more frequently employed than
         the corresponding terms chancery and court of chancery.
         --Burrill.
         [1913 Webster]

   Inns of chancery. See under Inn.

   To get (or to hold) In chancery (Boxing), to get the head
      of an antagonist under one's arm, so that one can pommel
      it with the other fist at will; hence, to have wholly in
      One's power. The allusion is to the condition of a person
      involved in the chancery court, where he was helpless,
      while the lawyers lived upon his estate.
      [1913 Webster]