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Onycha
Onycha [EBD]
a nail; claw; hoof, (Heb. sheheleth; Ex. 30:34), a Latin word applied to the operculum, i.e., the claw or nail of the strombus or wing-shell, a univalve common in the Red Sea. The opercula of these shell-fish when burned emit a strong odour "like castoreum." This was an ingredient in the sacred incense.
Onycha [NAVE]
ONYCHA, a component of the sacred ointment, made from the shells of a species of mussel, possessing an odor, Ex. 30:34.ONYCHA [SMITH]
spoken of in (Exodus 30:34) was one of the ingredients of the sacred perfume. It consists of the shells of several kinds of mussels, which when burned emit a strong odor.ONYCHA [ISBE]
ONYCHA - on'i-ka (shecheleth; compare Arabic suchalat, "filings," "husks"): "Onycha" is a transliteration of the Septuagint onucha, accusative of onux, which means "nail," "claw," "hoof," and also "onyx," a precious stone. The form "onycha" was perhaps chosen to avoid confusion with "onyx," the stone. The Hebrew shecheleth occurs only in Ex 30:34 as an ingredient of the sacred incense. It is supposed to denote the horny operculum found in certain species of marine gasteropod molluscs. The operculum is a disk attached to the upper side of the hinder part of the "foot" of the mollusc. When the animal draws itself into its shell, the hinder part of the foot comes last, and the operculum closes the mouth of the shell. The operculum, which may be horny or stony, is absent in some species. The horny opercula when burned emit a peculiar odor, and are still used in combination with other perfumes by the Arab women of Upper Egypt and Nubia. (See Sir S. Baker, The Nile Tributaries of Abyssinia, cited by EB, under the word "Onycha.")Alfred Ely Day
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