Original: In French '' Belle de Jour '' is an expression translating literally as '' beauty of ( the ) day , '' as opposed to '' femme de nuit '' or '' belle de nuit , '' women of the night ( common references to prostitutes ) .
Simplified: In French '' Belle de Jour '' means '' beauty of ( the ) day , '' as opposed to '' femme de nuit '' or '' belle de nuit , '' women of the night ( common references to prostitutes ) .