| American Football ConferenceThe American Football Conference (or AFC is one of the two conferences that compose the National Football League. The AFC was formed before the 1970 NFL season from the American Football League when it merged with the old National Football League, with th | AmphibiaSubclass Labyrinthodontia extinct Subclass Lepospondyli extinct Subclass Lissamphibia Urodela Anura Gymnophiona The class Amphibia consists of all tetrapods (four-legged vertebrates) that do not have amniotic eggs. Amphibians generally spend part of their | America the BeautifulAmerica the Beautiful is an American patriotic song and Christian hymn which rivals the national anthem of the United States, " The Star-Spangled Banner," in popularity. There was a movement during the John F. Kennedy administration to legally make "Ameri |
| American National Standards InstituteThe American National Standards Institute (ANSI) is a private, non-profit standards organization that produces industrial standards in the United States. It is a member of ISO and IEC. ANSI's standards fall in many areas. In computing, ANSI standardized t | AmbiguityA word, phrase, sentence, or other communication is called ambiguous if it can be reasonably interpreted in more than one way. The simplest case is a single word with more than one sense: The word "bank", for example, can mean "financial institution", "ed | Amateur astronomyAmateur astronomy often called back yard astronomy is a hobby whose participants enjoy observing celestial objects. It is usually associated with viewing the night sky when most celestial objects and events are visible, but sometimes amateur astronomers a |
| American footballAmerican football known in the United States simply as football is a competitive team sport that rewards players' speed, agility, skill, tactics, and brute strength as they run and throw a ball, and block, tackle, and outrun each other, trying to force th | American Revolutionary WarThe American Revolutionary War ( 1775 1783), also known as the American War of Independence was a war fought between Great Britain and revolutionaries within thirteen of her North American colonies. The war, which eventually widened far beyond British Nor | AmpereIn physics, the ampere (symbol: A often informally abbreviated to amp is the SI base unit used to measure electrical currents. The present definition, adopted by the 9th CGPM in 1948 is: "one ampere is that constant current which, if maintained in two str |
