roast beef noun4 •Beef cooked by roasting. •A cut of beef that has been roasted.I tell the waiter, 'We'll have two roast beefs, one well-done, the other medium rare.' — 2000 •A portion of roasted beef.Because there, in the middle of the table, among the roast beefs on rolls,[…] — 2006 •A cut of beef intended for roasting.Two or three times a week I had to deliver fifteen- or twenty-pound roast beefs to delis around the Bronx so that they could cook them and slice them up for sandwiches. — 1999 formsroast beefs