The term en femme [ɑ̃ fam] is a lexical borrowing of a French phrase. It is used in the transgender and crossdressing community to describe the act of wearing feminine clothing or expressing a stereotypically feminine personality. The term is borrowed from the modern French phrase en femme meaning "as a woman." Transgender and cross-dressing people may also use a female name whilst en femme; that is their "femme name". In the cross-dressing community the persona a man adopts when he dresses as a woman is known as his "femme self".
References
En femme Wikipedia(Text) CC BY-SA