I believe that the term wasfirst used when Christianity today was founded, as it meant that one held to essential truths of the faith, but also were not into separating from main culture, and also was involved in education and use of all of the tools available to us to study scriptures.This is the definition that we use:
"To say that we are evangelical means that we take our stand with all those who believe in what used to be called “the fundamentals”: the existence of the triune God, the deity of Jesus, the virgin birth, and substitutionary and vicarious atonement of Christ, the physical resurrection of Christ, the sure return of Christ, and the infallibility and divine authority of the Bible which is a faithful and true guide to what we are to believe and how we are to live. We joyfully affirm our unity with those from every tradition and denomination who hold to these fundamentals including those true believers in Christ who, for whatever reasons, find themselves members of denominations or churches with which we might have certain disagreements."