Apologist :: Apologist (n.) One who makes an apology; one who speaks or writes in defense of a faith, a cause, or an institution; especially, one who argues in defense of Christianity..
Apologize :: Apologize (v. i.) To make an apology or defense.
Apologize :: Apologize (v. i.) To make an apology or excuse; to make acknowledgment of some fault or offense, with expression of regret for it, by way of amends; -- with for; as, my correspondent apologized for not answering my letter..