The Collaborative International Dictionary of English v.0.48:

evangel \e*van"gel\ ([-e]*v[a^]n"j[e^]l), n. [F. ['e]vangile, L.
   evangelium, Gr. e'yagge`lion good news, glad tidings, gospel,
   fr. e'ya`ggelos bringing good news; e'y^ well + 'a`ggelein to
   bear a message. See Eu-, and Angel and cf. Evangely.]
   Good news; announcement of glad tidings; especially, the
   gospel, or a gospel. --Milton.
   [1913 Webster]

         Her funeral anthem is a glad evangel.    --Whittier.
   [1913 Webster]

WordNet (r) 3.0 (2006):

evangel
    n 1: the four books in the New Testament (Matthew, Mark, Luke,
         and John) that tell the story of Christ's life and
         teachings [syn: Gospel, Gospels, evangel]