Reference: HORSELEECH
American
The bloodsucker, a well-known water-worm; an apt emblem of avarice and rapacity, Pr 30:15. Cicero speaks of the horseleeches of the public treasury at Rome.
Morish
Leeches are abundant in Palestine, and the horseleech may simply refer to a large species that would settle on a horse's foot if placed in the water where they abound. A horse has been known, in drinking, to get a leech into its mouth, which immediately began to suck its blood. The leech is used symbolically of a rapacious person, who is never satisfied, graphically delineated by the leech's two daughters, who say, 'Give, give.' Pr 30:15.
Smith
Horse-leech,
Heb. 'alukah, occurs once only, viz.
There is little doubt that 'alukah denotes some species of leech, or rather is the generic term for any blood-sucking annelid.