The Collaborative International Dictionary of English v.0.48:

Instance \In"stance\, n. [F. instance, L. instantia, fr.
   instans. See Instant.]
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   1. The act or quality of being instant or pressing; urgency;
      solicitation; application; suggestion; motion.
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            Undertook at her instance to restore them. --Sir W.
                                                  Scott.
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   2. That which is instant or urgent; motive. [Obs.]
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            The instances that second marriage move
            Are base respects of thrift, but none of love.
                                                  --Shak.
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   3. Occasion; order of occurrence.
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            These seem as if, in the time of Edward I., they
            were drawn up into the form of a law, in the first
            instance.                             --Sir M. Hale.
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   4. That which offers itself or is offered as an illustrative
      case; something cited in proof or exemplification; a case
      occurring; an example; as, we could find no instance of
      poisoning in the town within the past year.
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            Most remarkable instances of suffering. --Atterbury.
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   5. A token; a sign; a symptom or indication. --Shak.
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   Causes of instance, those which proceed at the solicitation
      of some party. --Hallifax.

   Court of first instance, the court by which a case is first
      tried.

   For instance, by way of example or illustration; for
      example.

   Instance Court (Law), the Court of Admiralty acting within
      its ordinary jurisdiction, as distinguished from its
      action as a prize court.

   Syn: Example; case. See Example.
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Bouvier's Law Dictionary, Revised 6th Ed (1856):

INSTANCE COURT, Eng. law. The English court of admiralty is divided into two
distinct tribunals; the one having, generally, all the jurisdiction of the
admiralty, except in prize cases, is called the instance court; the other,
acting under a special commission, distinct from the usual commission given
to judges of the admiralty, to enable the judge in time of war to assume the
jurisdiction of prizes, and' called Prize court.
     2. In the United States, the district courts of the U. S. possess all
the powers of courts of admiralty, whether considered as instance or prize
courts. 3 Dall. R. 6. Vide 1 Gall. R. 563; Bro. Civ. & Adm. Law, ch. 4 & 5;
1 Kent, Com. 355, 378. Vide Courts of the United States; Prize Court.