Irony

Irony is commonly used in U.S. English to refer to a type of rhetoric whereby a statement or assertion is made with the intention to put across the opposite meaning. E.g. "Oh I really like your coat." In British English this is more commonly refered to as sarcasm.

In British English, irony refers to an action or occurence that is incongruous or amusingly unexpected. An example of this definition of irony might be a boxer betting his life savings on a fight he expects to lose, and then accidentally winning the fight.