Source : Webster's Revised Unabridged Dictionary (1913)

Precedent \Pre*ced"ent\, a. [L. praecedens, -entis, p. pr. of
   praecedere: cf. F. pr['e]c['e]dent. See {Precede}.]
   Going before; anterior; preceding; antecedent; as, precedent
   services. --Shak. ``A precedent injury.'' --Bacon.

   {Condition precedent} (Law), a condition which precede the
      vesting of an estate, or the accruing of a right.

Precedent \Prec"e*dent\, n.
   1. Something done or said that may serve as an example to
      authorize a subsequent act of the same kind; an
      authoritative example.

            Examples for cases can but direct as precedents
            only.                                 --Hooker.

   2. A preceding circumstance or condition; an antecedent;
      hence, a prognostic; a token; a sign. [Obs.]

   3. A rough draught of a writing which precedes a finished
      copy. [Obs.] --Shak.

   4. (Law) A judicial decision which serves as a rule for
      future determinations in similar or analogous cases; an
      authority to be followed in courts of justice; forms of
      proceeding to be followed in similar cases. --Wharton.

   Syn: Example; antecedent.

   Usage: {Precedent}, {Example}. An example in a similar case
          which may serve as a rule or guide, but has no
          authority out of itself. A precedent is something
          which comes down to us from the past with the sanction
          of usage and of common consent. We quote examples in
          literature, and precedents in law.

Source : WordNet®

precedent
     n 1: an example that is used to justify similar occurrences at a
          later time [syn: {case in point}]
     2: (civil law) a law established by following earlier judicial
        decisions [syn: {case law}, {common law}]
     3: a system of jurisprudence based on judicial precedents
        rather than statutory laws; "common law originated in the
        unwritten laws of England and was later applied in the
        United States" [syn: {common law}, {case law}]
     4: a subject mentioned earlier (preceding in time)

precedent
     adj : preceding in time, order, or significance