preexist

from WordNet (r) 3.0 (2006)

preexist
    v 1: exist beforehand or prior to a certain point in time; "Did
         this condition pre-exist?"

from The Collaborative International Dictionary of English v.0.48

Preexist \Pre`["e]x*ist"\, v. i. [imp. & p. p. {Pre["e]xisted};
   p. pr. & vb. n. {Pre["e]xisting}.]
   To exist previously; to exist before something else; to exist
   before the current activity commenced; as, preexisting
   illnesses are not covered by this insurance policy. [Also
   spelled {pre-exist}.]
   [1913 Webster + WordNet 1.5 + PJC]