A mannequin is a good-looking, admirably formed young lady, whose mission is to dress herself in her employer's latest "creations," and to impart to them the grace which only perfect forms can give. Her grammar may be bad, and her temper worse, but she must have the chic the Parisienne possesses, no matter whether she hails from the aristocratic Faubourg St. Germain or from the Faubourg Montmartre. ["The Bystander," Aug. 15, 1906]
Later (by 1939) of artificial model figures to display clothing.
Under bad manners, as under graver faults, lies very commonly an overestimate of our special individuality, as distinguished from our generic humanity. [Oliver W. Holmes, "The Professor at the Breakfast Table," 1858]
Earlier it meant "moral character" (early 13c.).