Horse-leech
Heb. 'alukah, occurs once only, viz. Pr 30:16 There is little doubt that 'alukah denotes some species of leech, or rather is the generic term for any blood-sucking annelid.
Bibliography Information Smith, William, Dr "Definition for 'Horse-leech' Smiths Bible Dictionary". bible-history.com - Smiths; 1901.