oxymoron n., pl. -mora. A rhetorical figure in which an epigrammatic effect is created by the conjunction of incongruous or contradictory terms; for example, "a mournful optimist." [Greek oxumoron, a clever remark, more pointedly witty for seeming absurd or foolish, neuter of oxumoros, "sharp-foolish": OXY- (sharp) + moros, stupid, foolish.
Oxymorons have been around for a long time. As you can see from the etymology above, the Greeks probably had a lot of fun with them. Comedian George Carlin has entertained us with his "airplane food," "postal service," " military intelligence," and "government worker." Below is a list that can continue to grow as new examples are added over time. Some oldies begin the list and a wild assortment of creative, albeit demented, minds have contributed to the rest.
Sweet sorrow Uncontrollable restraint Marital bliss Adequate incompetence Frenzied indifference Unquestionable doubt Thunderous silence Selfish generosity Greater reduction Intricate simplicity Impending uncertainty Willing reluctance The fame of anonimity Adulterous fidelity Dynamic serenity Incisive indecision Platonic fornication Stringent permissiveness Harmonious cacophony Marginal infinity Flagrant timidity Articulate ambiguity Courageous apprehension Rational dementia Meteroic demise Benign malignancy Emphasized understatement Terrifyingly placid Intuitive inaccuracy Apathetic sympathy Crowded seclusion Meticulous carelessness Humble egotist Impregnable vulnerability Humorous lament