Source : Webster's Revised Unabridged Dictionary (1913)

Incident \In"ci*dent\, a. [L. incidens, -entis, p. pr. & of
   incidere to fall into or upon; pref. in- in, on + cadere to
   fall: cf. F. incident. See {Cadence}.]
   1. Falling or striking upon, as a ray of light upon a
      reflecting surface.

   2. Coming or happening accidentally; not in the usual course
      of things; not in connection with the main design; not
      according to expectation; casual; fortuitous.

            As the ordinary course of common affairs is disposed
            of by general laws, so likewise men's rarer incident
            necessities and utilities should be with special
            equity considered.                    --Hooker.

   3. Liable to happen; apt to occur; befalling; hence,
      naturally happening or appertaining.

            All chances incident to man's frail life. --Milton.

            The studies incident to his profession. --Milward.

   4. (Law) Dependent upon, or appertaining to, another thing,
      called the principal.

   {Incident proposition} (Logic), a proposition subordinate to
      another, and introduced by who, which, whose, whom, etc.;
      as, Julius, whose surname was C[ae]sar, overcame Pompey.
      --I. Watts.

Incident \In"ci*dent\, n. [Cf. F. incident.]
   1. That which falls out or takes place; an event; casualty;
      occurrence.

Source : WordNet®

incident
     adj 1: falling or striking on something
     2: (sometimes followed by `to') minor or casual or subordinate
        in significance or nature or occurring as a chance
        concomitant or consequence; "incidental expenses"; "the
        road will bring other incidental advantages"; "extra
        duties incidental to the job"; "labor problems incidental
        to a rapid expansion"; "confusion incidental to a quick
        change" [syn: {incidental}] [ant: {basic}]

incident
     n 1: a single distinct event
     2: a public disturbance; "the police investigated an incident
        at the bus station"