Oonagh
pronounced OU-naOonagh means “lamb.”
Not in Ireland's 2025 tables (fewer than three babies); last recorded in 2024.
More about OonaghIrish Girl Names Starting with O
3 Irish girl names beginning with O, with what each one means and how to say it.
Updated October 2026
Irish girl names starting with O
Orla in Irish is Orlaith, meaning “golden princess.” Say it OR-la.
No. 189 for girls in Ireland in 2025, with 23 baby girls.
More about OrlaOrlaith
pronounced OR-laOrlaith comes from the Irish Órlaith (older Órfhlaith), from ór “gold” and flaith “ruler, prince,” which is read as “princess” in women’s names, so “golden princess.” Patrick Woulfe’s Irish Names and Surnames (1923) glosses it as “the golden lady.” Orla and Orlagh are the anglicized forms.
No. 325 for girls in Ireland in 2025, with 12 baby girls.
More about OrlaithThere are 3 Irish girl names starting with O here. The ones readers look up most are Orla, Oonagh and Orlaith.