The Greek New Testament term, from which our modern word derives, means an announcement of good news. A herald's joyful cry.
In NT usage, it refers specifically to what we call the Gospel--the euangellion--the good news of the life, death, and resurrection of Jesus Christ.
When Martin Luther broke away from the Roman Church in the Reformation, he initially intended his followers to be called "Evangelicals." He meant to identify those who believed in grace alone, through faith alone, in Christ alone.
Unfortunately, the term did not stick, and his movement became known as the Lutheran movement.
Today, however, the term has lost all formal resemblance to either NT or Reformation usage. It has become a "wax nose," able to be shaped and reshaped as one pleases. For some, it is a voting block of conservatives (most often associated with the Republican Party).
For others, it means non-denominational Christianity, i.e. generic doctrine divorced from the specificity of credal and confessional Christianity.
J.C. Ryle (1816-1900) gave one of the best warnings I have heard regarding this kind of doctrinally vague Christianity. He said, generic doctrine...
"...is an epidemic which is just now doing great harm, and especially among young people. . . . It produces what I must venture to call . . . a 'jelly-fish' Christianity . . . a Christianity without bone, or muscle, or power. . . . Alas! It is a type of much of the religion of this day, of which the leading principle is, 'no dogma, no distinct tenets, no positive doctrine.'
We have hundreds of 'jellyfish' clergyman, who seem not to have a single bone in their body of divinity. They have no definite opinions . . . they are so afraid of 'extreme views' that they have no views of all.
We have thousands of 'jellyfish' sermons preached every year, sermons without an edge, or a point, or corner, smooth as billiard balls, awakening no sinner, and edifying no saint. . . .
And worst of all, we have myriads of 'jellyfish' worshipers—respectable Church-gone people, who have no distinct and definite views about any point in theology. They cannot discern things that differ, any more than colorblind people can distinguish colors. . . . They are 'tossed to and fro, like children, by every wind of doctrine'; . . . ever ready for new things, because they have no firm grasp on the old."(1)
If by "evangelical" you mean the strand of believer who holds fast despite the cost to the great and ancient doctrines of the NT: atonement, justification, repentance etc, count me as one.
But if by "evangelical" you mean a generic, feel good, self-improvement, entertainment-based form of Christianity, then just call me Reformed.
Matthew Everhard is the Senior Pastor of Faith Evangelical Presbyterian Church in Brooksville, Florida.
(1) From an excellent sermon on the life of J.C. Ryle by John Piper. http://www.desiringgod.org/resource-library/biographies/the-frank-and-manly-mr-ryle-the-value-of-a-masculine-ministry