That part of a theater stage floor on which the actors perform.

A curtain, behind the asbestos curtain in a theater, which closes the proscenium and serves as an indication of the

On drawings, abbreviation for actual

Abbr. for American Ceramic Society

A plastic used for piping in drainage systems, storm sewers, and underground electrical conduit.

One of a group of thermoplastic resins made from esters of acrylic acid; exceptionally tough, stable, resistant to chemicals, and

A synthetic fiber manufactured by polymerizing acrylonitrile.