roomful n 1: the quantity a room will hold
Roomful \Room"ful\, a. Abounding with room or rooms; roomy. "A roomful house." [R.] --Donne. [1913 Webster]
Roomful \Room"ful\, n.; pl. {Roomfuls}. As much or many as a room will hold; as, a roomful of men. --Swift. [1913 Webster]