Green’s Dictionary of Slang

shirley n.

[proper name of US actress and gay icon (esp. in her roles as a 1930s child star) Shirley Temple (b.1928)]

1. (US) a gay man.

[US]R. Campbell Alice in La-La Land (1999) 12: This hard type tried to pick up a shirley with a Valentino hairdo wearing the uniform of a World War One Flyer and got turned down.

2. see sheila n.1 (2)