The Collaborative International Dictionary of English v.0.48:

Beefsteak \Beef"steak`\ (b[=e]f"st[=a]k), n.
   A steak of beef; a slice of beef broiled or suitable for
   broiling.
   [1913 Webster]

WordNet (r) 3.0 (2006):

beefsteak
    n 1: a beef steak usually cooked by broiling

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "beefsteak":
   London broil, Salisbury steak, T-bone steak, bifteck,
   chopped steak, club steak, cubed steak, fillet steak, flank steak,
   ground beef, ground chuck, ground round, hamburg, hamburg steak,
   hamburger, porterhouse steak, rib steak, round steak, rump steak,
   shell steak, sirloin steak, steak, tenderloin steak