The Collaborative International Dictionary of English v.0.48:
Grillroom \Grill"room`\, n. 1. A room specially fitted for broiling food, esp. one in a restaurant, hotel, or clubhouse, arranged for prompt service. [Webster 1913 Suppl.] 2. a restaurant where food is cooked on a grill. [WordNet sense 1] Syn: grill. [WordNet 1.5]WordNet (r) 3.0 (2006):
grillroom n 1: a restaurant where food is cooked on a grill [syn: grillroom, grill]