hors'-lech (`aluqah; compare Arabic `aluqah, "ghoul," and `alaqah, "leech," from root `aliq, "to cling"; Septuagint bdella, "leech"): The word occurs only once, in Pr 30:15, the Revised Version margin "vampire." In Arabic `alaqah is a leech of any kind, not only a horse-leech. The Arabic `aluqah, which, it may be noted, is almost identical with the Hebrew form, is a ghoul (Arabic ghul), an evil spirit which seeks to injure men and which preys upon the dead. The mythical vampire is similar to the ghoul. In zoology the name "vampire" is applied to a family of bats inhabiting tropical America, some, but not all, of which suck blood. In the passage cited the Arabic Bible has `aluqah, "ghoul." If leech is meant, there can be no good reason for specifying "horseleach." At least six species of leech are known in Palestine and Syria, and doubtless others exist. They are common in streams, pools, and fountains where animals drink. They enter the mouth, attach themselves to the interior of the mouth or pharynx, and are removed only with difficulty.
Alfred Ely Day