A boy that purposely dresses in a girly fashion. Most commanly seen today in the tight-pants-wearing "skater" population. They sport smooth chin length haircuts with long bangs that hang down across their eyes. A true femmy boy has androgynous facial features and will spend numerous hours plucking his eyebrows.
(adj.) Used to describe a person, especially a male, who seems to embody many female characteristics and mannerisms. Is not necessarily derrogative, just descriptive.