Reference to "Of Mice and Men", namely the ending where George tells Lennie to look at the rabbits so he can shoot Lennie while he's not looking. Basically means the same thing as go play in traffic; go jump off a cliff, die, etc. in addition to calling the person a retard. Could also be interpreted as a threat.

Referring to women who are sexually or romantically attracted to other women. Applies to both lesbians and bisexual women, as it is only the same-sex attraction that matters, not any other attractions the women may have.

Originates from the Greek poet Sappho, a bisexual woman from the Isle of Lesbos, from which we get the term lesbian.