Richard Nixon was an apologist. Saint Paul was an apologetic.
Someone above asked if "theologian" was the same thing as "apologist". I think the answer is "sometimes and sort of". One of the greatest Christian theologians in history was St. Thomas Aquinas, and most of his works could be categorized as "apologetics," because they are specifically interested in defending the faith against various objections.
In fact, they're structured according to a particular method: State the objection(s) ("It is said that ..."), state the teaching ("But I say that ..."), then refute the objections individually.
There are theologians who don't really fit the bill as apologists, and there are theologians who look down their noses at apologists as well.
Apologist or Apologetic?
You may ignore this comment!
(Forgive me but I am a language maven above all else, going so far as to miss the whole point of discussion by tracking some term of expression. If I seem to claim authority, I don’t mean to. I relate my observations and beg correction and contradiction. I am descriptivist, and not prescriptivist, and heaven forfend, one must never be proscriptivist! When you correct, please include the reasoning with my many thanks.)
English having so much vocabulary, any word can become attached to narrow connotation. One comment suggested, “I have nothing to apologize for.” Quickly someone corrected, but gradually fewer people correct and the usage change takes hold.
In current usage, please correct me, an “apologist” is one who speaks in defense of anything in a controversy. An “apologetic” is one who specializes in all aspects of the field of Christian apologetics. “Apologetic” as a noun in this sense is not in the dictionary yet. My Webster’s connects “apologetic” as a singular to the term “apologetics”. “Apologist” is still the correct term, but in fundamentalist or evangelical lingo, whether you say, “Ravi Zacharias, the Christian apologetic, has passed away” or “the Christian apologist”, you will probably not be corrected either way.
Google results showed an example from Twitter of “Ravi Zacharias, Christian Apologetic” and all others were “...Apologist” On that Twitter feed, “apologetic” used in this sense was routine but there was one correction, “I think we should speak the truth courageously and not be so apologetic.” This was largely ignored. One tweet praising Ravi played on the definition, “We need a Christian apologetic that is heard and seen.”
We would not use the verb “apologize” for making the argument, since other verbs more clearly specify the nature of the defense, e.g. “answer” or “argue” or “defend” etc. We do still use the word “apology” to mean the specific argument. You can argue any argument in your argument argumentatively, but you must never argue any apologetic in your apologetics, apologetically.
Proper apologizing must admit and take responsibility for the wrong.
Fred: “Hey Barney. I wanna apologize to you.”
Barney: “Huh? OK what is it?”
Fred: “Well I’m sorry ya took it wrong about Betty, but ya shouldn’t have jumped to conclusions.”
Barney: “Errr...dat ain’t no apology Fred.”
Fred: “Dagnabit Barn, I knew there was no point tryin’ to apologize to you!”
So the larger point, without apology I say that Ravi, the exemplary theodicist, was a hero to all Christian apologists, even an excellent apologist for apologetics, whenever someone would scold, “Bless God, just preach the Word!”
He will be missed.