Source : Webster's Revised Unabridged Dictionary (1913)

Coexist \Co`ex*ist\, v. i. [imp. & p. p. {Coexisted}; p. pr. &
   vb. n. {Coexisting}.]
   To exist at the same time; -- sometimes followed by with.

         Of substances no one has any clear idea, farther than
         of certain simple ideas coexisting together. --Locke.

         So much purity and integrity . . . coexisting with so
         much decay and so many infirmities.      --Warburton.

Source : WordNet®

coexist
     v 1: coexist peacefully, as of nations
     2: exist together