An Oxymoron is two words, or a compound word, with contradictory definitions. The most commonly-used example of an oxymoron is 'jumbo shrimp,' as a shrimp is small by definition and therefore cannot be jumbo.
More oxymorons:
Government ethics
Friendly fire
Pretty ugly United Nations
Hamburger
Urban Dictionary Holy war
McDonald's Big N' Tasty
Microsoft Works
Rap Music Jumbo Shrimp Plastic Glasses
Peace Force
Good Grief
Personal Computer
Random Order
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