Wiktionary
n. Any of a variety of high-performance automobiles, especially American 2-door rear wheel drive mid-size cars of the late 1960s and early 1970s equipped with large, powerful V8 engines.
Wikipedia
Muscle car is an American term used to refer to a variety of high-performance automobiles. The Merriam-Webster dictionary defines muscle cars as "any of a group of American-made 2-door or 4-door sports cars with powerful engines designed for high-performance driving." A large V8 engine is fitted in a 2-door, rear wheel drive, family-style mid-size or full-size car designed for four or more passengers. Sold at an affordable price, muscle cars are intended for street use and occasional drag racing. They are distinct from two-seat sports cars and expensive 2+2 GTs intended for high-speed touring and road racing.
Usage examples of "muscle car".
It was a muscle car, a Plymouth Roadrunner, red as a candy apple, half a block away.
She was conscious of the attention she was getting from the three young men in the muscle car.
He was driving slowly, looking at names on mailboxes to be sure he found the right place, when a white muscle car exploded from a stand of trees and came at him.
This put the picture at eye-level to him, and he studied it eagerly, once again taken by the simpleminded weirdness of the subject: kid behind the wheel of a muscle car, a kid with a nasty, knowing grin that revealed the filed points of an even nastier set of teeth.
Thinking of when her father had bought her the '69 muscle car, a junker, and how together they'd rebuilt much of the engine and suspension, added a new transmission, and stripped it, to goose the horsepower skyward.
Fernando navigated the complicated neighborhood street plan, his friends tailing us in the muscle car, until we found the address.
What held his interest was the old muscle car, a Python with smoked glass windows.