The Collaborative International Dictionary of English v.0.48:

Jury \Ju"ry\, a. [Etymol. uncertain.] (Naut.)
   For temporary use; -- applied to a temporary contrivance.
   [1913 Webster]

   Jury rudder, a rudder constructed for temporary use.
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The Collaborative International Dictionary of English v.0.48:

Jury \Ju"ry\, n.; pl. Juries. [OF. jur['e]e an assize, fr.
   jurer to swear, L. jurare, jurari; akin to jus, juris, right,
   law. See Just,a., and cf. Jurat, Abjure.]
   [1913 Webster]
   1. (Law) A body of people, selected according to law,
      impaneled and sworn to inquire into and try any matter of
      fact, and to render their true verdict according to the
      evidence legally adduced. In criminal trials the number of
      such persons is usually twelve, but in civil cases and in
      grand juries it may different. See Grand jury under
      Grand, and Inquest.
      [1913 Webster +PJC]

            The jury, passing on the prisoner's life. --Shak.
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   2. A committee for determining relative merit or awarding
      prizes at an exhibition or competition; as, the art jury
      gave him the first prize.
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   Jury of inquest, a coroner's jury. See Inquest.
      [1913 Webster]

WordNet (r) 3.0 (2006):

jury
    n 1: a body of citizens sworn to give a true verdict according
         to the evidence presented in a court of law
    2: a committee appointed to judge a competition [syn: jury,
       panel]

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

JURY. A body of men selected according to law, for the purpose of deciding
some controversy.
     2. This mode of trial by jury was adopted soon after the conquest of
England, by William, and was fully established for the trial of civil suits
in the reign of Henry II. Crabb's C. L. 50, 61. In the old French law they
are called inquests or tourbes of ten men. 2 Loisel's Inst. 238, 246, 248.
     3. Juries are either grand juries, (q.v.) or petit juries. The former
having been treated of elsewhere, it will only be necessary to consider the
latter. A petit jury consists of twelve citizens duly qualified to serve on
juries, impanelled and sworn to try one or more issues of facts submitted to
them, and to give a judgment respecting the same, which is called a verdict.
     4. Each one of the citizens so impanelled and sworn is called a juror.
Vide Trial.
     5. The constitution of the United States directs, that "the trial of
all crimes, except in cases of impeachment, shall be by jury;" and this
invaluable institution is also, secured by the several state constitutions.
The constitution of the United States also provides that in suits at common
law, where the value in controversy shall exceed twenty dollars, the right
of trial by jury shall be preserved. Amend. VII.
     6. It is scarcely practicable to give the rules established in the
different states to secure impartial juries; it may, however, be stated that
in all, the selection of persons who are to serve on the jury is made by
disinterested officers, and that out of the lists thus made out, the jurors
are selected by lot.