Real Dictionary

curtsy
verb: If a woman or a girl curtsies, she lowers her body briefly, bending her knees and sometimes holding her skirt with both hands, as a way of showing respect for an important person.

curtsy in American English
a gesture of greeting, respect, etc. made, esp. formerly, by girls and women and characterized by a bending of the knees and a slight lowering of the body
intransitive verb: to make a curtsy
noun: a respectful bow, traditionally made by women and girls, consisting of bending the knees and lowering the body

curtsy in British English
noun: a formal gesture of greeting and respect made by women in which the knees are bent, the head slightly bowed, and the skirt held outwards
verb: to make a curtsy