Muscle car is a description according to Merriam-Webster Dictionary that came to use in 1966 for "a group of American-made two-door sports coupes with powerful engines designed for high-performance driving." The Britannica Dictionary describes these as "an American-made two-door sports car with a powerful engine."
Although the term was unknown for another fifteen-plus years, General Motors is credited by some as introducing the first "intentional" muscle car in 1949, when it put its 303-cubic-...