Femme Osage is an unincorporated community in southwest St. Charles County, in the U.S. state of Missouri. [1] The community is on Missouri Route T along the bank of the Femme Osage Creek. [2]
A post office Femme Osage was in operation from 1816 until 1933. [3] The community takes its name from nearby Femme Osage Creek. [4]