A boudoir (/ˈbuːdwɑːr/; French: [bu.dwaʁ]) is a woman's private sitting room or salon in a furnished accommodation usually between the dining room and the bedroom, but can also refer to a woman's private bedroom. The term derives from the French verb bouder to sulk, or boudeur sulk or sulking, and originally was a room for sulking in, to put away or withdraw to.
The Marquis de Sade (1740-1814) in his literary works helped develop a reputation in this small room dedicated to the privacy of female talks. Since the success of his book Philosophy in the Bedroom, the small sitting room or salon has a scandalous reputation combined with those of all exchanges and frolics.
A cognate of the English "bower", historically, the boudoir formed part of the private suite of rooms of a "lady" or upper-class woman, for bathing and dressing, adjacent to her bedchamber, being the female equivalent of the male cabinet. In later periods, the boudoir was used as a private drawing room, and was used for other activities, such as embroidery or spending time with one's romantic partner.
English-language usage varies between countries, and is now largely historical. In the United Kingdom, in the period when the term was most often used (Victorian era and early 20th century), a boudoir was a lady's evening sitting room, and was separate from her morning room, and her dressing room. As this multiplicity of rooms with overlapping functions suggests, boudoirs were generally only found in grand houses. In the United States, in the same era, boudoir was an alternative term for dressing room, favored by those who felt that French terms conferred more prestige.