This obscure term appears in the Nazirite regulations, specifying that one under the vow must avoid eating anything from the grape vine, 'from the seeds to the skin.' The exact identification is uncertain—possibly the transparent outer skin of the grape. The Mishnah preserves the term with the same meaning. Rabbinic sources connect it to words for 'glass' (זְגוּגִית), suggesting transparency as the linking concept. The term's rarity makes precise definition difficult, but the context clearly involves grape products forbidden to Nazirites.