lesbian sheep

(metaphor) Not making your move towards someone you love, for whatever it may be—staying still when you are forced to make a move in a situation.

This is taken from the thought that a homosexual ewe cannot be found in the wild because when heterosexual ewe mate, they stand still. So, a gay ewe would do nothing, even when wanting to mate.

(literal) A homosexual ewe.

(metaphor) Dad: My son told me he had a crush on a girl in his class, but acted the lesbian sheep and didn't make his move.

(literal) Farmer: We've had these sheep for a while, they've always been very close, but never have tried to mate with the males. We think they're just lesbian sheep.