Use of the word has been practiced and advocated to distinguish U.S. nationals from people living in other countries in the Americas. The concern that motivates use of the word is that, since "America" is part of the names of both North America and South America, it follows that "American" means, or ought to be understood to mean, "inhabitant of the Americas".
Other words that have been suggested for the same purpose are Columbian, Columbard, Fredonian, Frede, Unisian, United Statesian, Colonican, Appalacian, Usian, Washingtonian, Usonian (among whose users was Frank Lloyd Wright), Uessian, U-S-ian, and Uesican (in approximately historical order from 1789 to 1939, according to Merriam Webster's Dictionary of English Usage).
Other examples observed in the field:
See also
Links and references: