Milfie, pronounces milfy, is the female version of MILF (Man I'd like to fuck). A milfie is basically the female version of MILF. It is a very attractive and sexy woman and when you call someone a milfie, you are giving signs for wanting sex. The phrase is often used by teenagers nowadays because they don't want to let their parents know what they are talking about
"Woah, she is a milfie"
"Have you seen milfie's boobs?"
"I wanna fuck that milfie"