The stage of an ancient Greek or Roman theater.
The part of the stage that is in front of the curtain.
The wall that separates the stage from the auditorium and provides the arch that frames it.
The other night the proscenium in the theater was beautifully constructed.
Literary Use of Word
The other spectators can't see anything beyond the proscenium and it's fair to say they'd rather not.(Wimmer 122)
Wimmer, Natasha. 2666: a Novel by Roberto Bulano. New York: Picador, 2009.