i Register
In some senses, onycha is marked as obsolete. Watch for register when choosing this word.
noun
the operculum of kinds of strombus or muricid, smoked as an ingredient in the Mosaic incense and pre-modern medicine
And our Lord ſaid to Moyſes: Take vnto thee ſpices, ſtactee, and onycha, galbanum of ſwete ſauour, and the cleareſt frankincenſe, al shal be of equal weight:
The precious stone onyx.