leaning board

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An item of furniture which is comparable in structure to a flat bench but positioned at a vertical diagonal. Often with attached arm rests. Used primarily in movie making and popularized in the early era of Hollywood; the purpose was for actresses in elaborate costumes, hair and makeup to be able to rest their bodies (or even sleep) without becoming disheveled, or in situations when their costume prohibited sitting down.