Oxymoron is a combination of two words in which the meaning is opposite in sense.
e. g. speaking silence, cold fire, living death.
Close to oxymoron is paradox - a statement that is absurd on the surface. e.g. War is peace. The worse - the better.
Trite oxymoron. e.g. Awfully beautiful.
If the primary meaning of qualifying word changes the stylistic effect of oxymoron is lost. In oxymoron the logical meaning holds fast because there is no true word combination.