proscenium
noun
pro·sce·ni·um prō-ˈsē-nē-əm 
1
a
: the stage of an ancient Greek or Roman theater
b
: the part of a modern stage in front of the curtain
c
: the wall that separates the stage from the auditorium and provides the arch that frames it
2
a
: foreground sense 1
b
: foreground sense 2
Example Sentences
The host walked onto the proscenium.
Recent Examples on the Web Located on the south end of the complex, its proscenium is framed by the skeletal remnants of the original east shed. 
Bob Gendron, Chicago Tribune, 3 Aug. 2022 The gleaming metal bas-reliefs above the proscenium arch are pure ‘30s swank. Mark Feeney, BostonGlobe.com, 6 May 2022 But the play was built for a proscenium stage, not three-quarter seating, and McCallum and his designers sometimes struggle to make the action visible to all, particularly in the final act. New York Times, 27 July 2022 Under a proscenium arch in the foyer, a marble staircase is inlaid with colorful mosaics. E.b. Solomont, WSJ, 5 May 2022 And Minnelli is clearly aware of the force of her performance, creating long takes that serve as a sort of proscenium as well as urgent closeups that burst with her tremulous power. Richard Brody, The New Yorker, 10 June 2022 Electronic auras seem to swirl around the audience, aided by the two antiphonal groups in the balcony boxes on either side of the proscenium — each with a percussionist, clarinetist and trumpeter. New York Times, 15 May 2022 Freedom feels ever more tangible when there are no walls around you, the artists have escaped the proscenium frame, and set design is left up to the sun, sky and birds. Sarah L. Kaufman, Washington Post, 2 June 2022 Perhaps Hartford Stage is the wrong space for it, with a thrust stage that doesn’t neatly accommodate old-fashioned proscenium-style living room sets. Christopher Arnott, Hartford Courant, 19 Apr. 2022 See More
Bob Gendron, Chicago Tribune, 3 Aug. 2022 The gleaming metal bas-reliefs above the proscenium arch are pure ‘30s swank. Mark Feeney, BostonGlobe.com, 6 May 2022 But the play was built for a proscenium stage, not three-quarter seating, and McCallum and his designers sometimes struggle to make the action visible to all, particularly in the final act. New York Times, 27 July 2022 Under a proscenium arch in the foyer, a marble staircase is inlaid with colorful mosaics. E.b. Solomont, WSJ, 5 May 2022 And Minnelli is clearly aware of the force of her performance, creating long takes that serve as a sort of proscenium as well as urgent closeups that burst with her tremulous power. Richard Brody, The New Yorker, 10 June 2022 Electronic auras seem to swirl around the audience, aided by the two antiphonal groups in the balcony boxes on either side of the proscenium — each with a percussionist, clarinetist and trumpeter. New York Times, 15 May 2022 Freedom feels ever more tangible when there are no walls around you, the artists have escaped the proscenium frame, and set design is left up to the sun, sky and birds. Sarah L. Kaufman, Washington Post, 2 June 2022 Perhaps Hartford Stage is the wrong space for it, with a thrust stage that doesn’t neatly accommodate old-fashioned proscenium-style living room sets. Christopher Arnott, Hartford Courant, 19 Apr. 2022 See More Word History
Etymology
Latin, from Greek proskēnion front of the building forming the background for a dramatic performance, stage, from pro- + skēnē building forming the background for a dramatic performance — more at scene
First Known Use
1606, in the meaning defined at sense 1a