A Japanese girl or young (especially unmarried) woman; a Japanese waitress, maid, or mistress.
Origin
Mid 19th century; earliest use found in Christopher Pemberton Hodgson (1821–1865), traveller. From Japanese musume daughter, girl from (u)musu to be born, to grow + me female. For the loss of the partially devoiced medial vowel compare moxa. Compare French musmé, mousmé.