padded cell

plural padded cells

1. idiomaticA room in a mental hospital lined with padding on the walls, and often a cushioned floor, in order to prevent occupants from injuring themselves.

   Ernie looked completely frazzled to Bill, fried; ready for a straight jacket and a padded cell.

   2006, Thomas Lee Cook, Jack Crocker: Catchin' the Con, page 180

   1 more example

   For the opening of the line 30 bogie coaches of the tramcar type were obtained from the Ashbury Railway Carriage & Iron Co. Ltd., of Manchester, and from their curious design, earned the nickname of "padded cells" owing to the upholstery being carried right up to the narrow slits which served as windows.

   1941 May, “Jubilee of the City Tube”, in Railway Magazine, page 224

   Synonyms: padded room, rubber room