Wiktionary
cube steak
n. A tenderized cut of beef, usually top round or top sirloin, used for example in chicken-fried steak.
Wikipedia
Cube steak
Cube steak is a cut of beef, usually top round or top sirloin, tenderized by fierce pounding with a meat tenderizer, or use of an electric tenderizer. The name refers to the shape of the indentations left by that process (called "cubing"). This is the most common cut of meat used for the American dish chicken fried steak.
Usage examples of "cube steak".
Of course he must also speak degenerate pidgin, as on the afternoon when Kelly was protesting the price of cube steak at the comer drug store.