an oxymoron is a figure of speech in which two words with opposing meanings are used together intentionally for effect or a paradoxical juxtaposition of two seemingly contradictory words.

The most common form of oxymoron involves an adjective-noun combination of two words.
The skydiver’s landing was almost exactly on target.

Sometimes it is in a phrase insted of just two words:
One bright day in the middle of the night,
Two dead boys got up to fight.
Back-to-back they faced one another,
Drew their swords and shot each other….

I think I will explore some oxymorons and share them in a few posts.

For more details, visit Wikipedia.