proscenium

UK: /prəˈsiːnɪəm/

US: /proʊˈsiniəm, prə-/

US: (prō sē′nē əm, prə-)

Inflections of 'proscenium' (n):

prosceniums

npl

proscenia

npl

WordReference Random House Learner's Dictionary of American English © 2026

pro•sce•ni•um /proʊˈsiniəm, prə-/   n. [countable] , pl. -ni•ums, -ni•a 

/-niə/.  
1. Show Business Also called proˈsce•ni•um ˌarch. the arch that separates a stage from the auditorium.

WordReference Random House Unabridged Dictionary of American English © 2026

pro•sce•ni•um  (prō sē′nē əm, prə-), n., pl. -ni•a (-nē ə). [Theat.]

1. Show Business Also called prosce′nium arch′. the arch that separates a stage from the auditorium. Abbr.: pros.
2. Show Business (formerly) the apron or, esp. in ancient theater, the stage itself.

• Greek proské̄nion entrance to a tent, porch, stage (Late Greek: stage curtain), equivalent. to pro- pro-² + skēn(é̄) (see scene) + -ion neuter noun, nominal suffix
• Latin proscēnium, proscaenium
• 1600–10

Collins Concise English Dictionary © HarperCollins Publishers::

proscenium / prəˈsiːnɪəm/ noun ( -nia / -nɪə/, -niums)

1. the arch or opening separating the stage from the auditorium together with the area immediately in front of the arch
2. (in ancient theatres) the stage itself

Etymology: 17th Century: via Latin from Greek proskēnion, from pro- before + skēnē scene