Mid 17th century; earliest use found in William Davenant (1606–1668), poet, playwright, and theatre manager. From post-classical Latin onychites or its etymon Hellenistic Greek ὀνυχίτηςonychites.
Definition of onychite in US English:
onychite
nounˈɒnɪkʌɪt
rare
Onyx marble.
Origin
Mid 17th century; earliest use found in William Davenant (1606–1668), poet, playwright, and theatre manager. From post-classical Latin onychites or its etymon Hellenistic Greek ὀνυχίτης onychites.