What does the expression “the daughter of the horseleech” mean and Where does it originate?

“The horseleech hath two daughters, crying, Give, give.”

You will find that in Proverbs, xxx, 15. Of course, the horseleech is an aquatic sucking worm, of large size and great sucking facilities which veterinary surgeons of old employed to remedy common diseases of the horse; hence, the name.

But the name, as far back as the sixteenth century, was therefore also applied to any veterinary surgeon and, because of the natural propensities of the worm itself, to any rapacious insatiable person, to any bloodsucker, clinging to another and robbing him of money, ideas, or other resources.

His daughters, presumably, are even more grasping; hence, any “daughter of a horseleech” is anyone, especially any female, who is constantly crying, “Give, give.”