Spinster
Part of speech: noun
Definition: An unmarried woman, especially one past the normal marrying age. One who spins (puts a spin on) a political media story so as to give something a favorable or advantageous appearance; a spin doctor, spin merchant or spin master. Someone whose occupation was spinning thread.
Bachelorette
Part of speech: noun
Definition: An unmarried woman.A very small bachelor (single room) apartment.