Answer:
Citizens of all countries on the both the North and South American continents are technically considered "residents of the America's," and therefore "americans" (with a small "a"). However, as it is generally applied, and understood to mean, "citizens of the United States Of America" - probably not. The term 'American,' (with a capital "A") refers to citizens of the only country on both continents which actually contains the word 'America' in it's country's official name.