roomful noun 2adjective 1forms 4 noun2 •The amount that a room can hold, especially the number of people that can fit into a room.Bengston doing a roomful of painting is like Joe Willie Namath doing a gameful of curl patterns, Jason Robards doing an eveningful of O'Neill, Tina Turner doing a concertful of. . . . and so on. — 1974 •The people in a room, considered as a group. adjective1 •Abounding with room or rooms; roomy.A roomful house. — 1612 formsroomfuls · roomsful · more roomful · most roomful