1828, "out of the ordinary course, forming an exception, unusual," from exception + -al (1). Related: Exceptionally. Exceptionalism "fact or quality of being exceptional" in some way, usually implying superiority to the unexceptional, is attested from 1864; the phrase American exceptionalism is attested by 1929, originally among communists, in reference to the argument about whether the United States is in some sense not subject to the historical rules of Marxism; it has been used in other ways since, often implying (and implicitly criticizing) a belief that the U.S. is somehow uniquely virtuous. Other noun forms include exceptionalness (1868), exceptionality (1851).