Curtsey

A curtsey (also spelled curtsy or even incorrectly courtsey) is a traditional gesture of greeting, in which a girl or woman bends her knees while bowing her head. It is the female equivalent of male bowing in Western cultures. Miss Manners characterizes its knee bend as deriving from a "traditional gesture of an inferior to a superior." The word "curtsy" is a phonological change from "courtesy" known in linguistics as syncope.