evangelist (n.) Look up evangelist at Dictionary.com
late 12c., "Matthew, Mark, Luke or John," from Old French evangelist and directly from Late Latin evangelista, from Greek euangelistes "preacher of the gospel," literally "bringer of good news," from euangelizesthai "bring good news," from eu- "good" (see eu-) + angellein "announce," from angelos "messenger" (see angel).

In early Greek Christian texts, the word was used of the four supposed authors of the narrative gospels. Meaning "itinerant preacher" was another early Church usage, revived in Middle English (late 14c.). Classical Greek euangelion meant "the reward of good tidings;" sense transferred in Christian use to the glad tidings themselves. In Late Latin, Greek eu- regularly was consonantized to ev- before vowels.