Sentence:  Below ground, in the maze of tunnels excavated by the rabbits over many, many years, five of our <WSD>jill</WSD>, or bitch, ferrets were running loose[...]. A white <WSD>jill</WSD> popped out of the hole nearest men slithered through the net mesh and disappeared down an adjacent entrance. 
Meaning of the word marked with <WSD> tags:  A female ferret.