A bloodsucking worm with a flat, segmented body that tapers at both ends but is broadest toward the posterior part. Leeches measure from over 1 cm (0.5 in.) to over 10 cm (4 in.) in length. These creatures have a disk, or sucker, at each end of the body, the one at the head end being equipped with biting jaws.
Leeches are found in great numbers in many streams and rivers of the Middle East. The young of one variety (Limnatis nilotica), when swallowed with the drinking water, attach themselves to the nasal cavities, larynx, or epiglottis of their host. They grow rapidly and are not easily removed. Their presence can hinder breathing and this, as well as loss of blood, sometimes proves fatal to the victim.
Sole mention is made of the leech (Heb., ʽalu·qahʹ) at Proverbs 30:15, where the reference is to insatiable greed, it being stated that “the leeches have two daughters that cry: ‘Give! Give!’” The Commentary by F. C. Cook suggests that the leech’s greed is here viewed as “its daughter,” spoken of in the plural to express intensity. Others consider the “two daughters” to be a reference to the two lips of its bloodsucking disk. A leech may consume three times its own weight in blood, a strong anticoagulant in its saliva ensuring a continuous flow from the victim.