- Origin: Italian
- Meaning: unknown
The male name Onelio is rare in Italy and appears mainly in Tuscany and Emilia-Romagna; its feminine forms of Onelia is slightly more common. Its origin is uncertain.
Some scholars connect it to the Ligurian city of Oneglia, which also produced the surnames Onelli and Onelio. Others link it to the Latin Honorius (“honourable”), while less common theories suggest the Latin alnus (“alder tree”) or the Old Germanic awi (“health”).
Italian immigrants introduced the name to Brazil, where it has occasional use.
Related masculine forms include Onello and Oneglio. The feminine counterpart is Onelia, with other variants such as Oneglia and Onella.
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