Source : Webster's Revised Unabridged Dictionary (1913)

Coincide \Co`in*cide"\, v. i. [imp. & p. p. {Coincided}; p. pr.
   & vb. n. {Coinciding}.] [L. co- + incidere to fall on; in +
   cadere to fall: cf. F. co["i]ncider. See {Chance}, n.]
   1. To occupy the same place in space, as two equal triangles,
      when placed one on the other.

            If the equator and the ecliptic had coincided, it
            would have rendered the annual revoluton of the
            earth useless.                        --Cheyne.

   2. To occur at the same time; to be contemporaneous; as, the
      fall of Granada coincided with the discovery of America.

   3. To correspond exactly; to agree; to concur; as, our aims
      coincide.

            The rules of right jugdment and of good
            ratiocination often coincide with each other.
                                                  --Watts.