Irish Girls First Names that Start with O

As you’re about to discover, there are lots of really original names for girls that start with O in ireland. You could go for something like Órlaith which was a royal name back in the day, or Órína which means ‘golden dawn’.

⭐ Our Favourite: Olwen (Ólwén)

Pronunciation: OL-wen
First Used: Early medieval period, rooted in Welsh and Irish mythology.
Meaning: Meaning “white footprint,” Olwen was a legendary figure in Welsh mythology, said to be so gentle that flowers grew where she walked. Though of Welsh origin, it aligns beautifully with Irish names and folklore.
Why It’s Our Favourite: Olwen has a magical, nature-infused quality that makes it feel both timeless and ethereal. It’s rare in Ireland yet fits seamlessly alongside Gaelic names. The idea of leaving beauty in one’s wake is a poetic and powerful symbol of grace and kindness.

🌿 Olivia (Oilibhia)

Pronunciation: uh-LIV-ee-uh
Meaning: A name of Latin origin, Olivia means “olive tree,” symbolizing peace and fruitfulness. Introduced to Ireland in recent centuries, it gained popularity after Shakespeare used it in Twelfth Night. It remains one of the most beloved names in Ireland today.

🏆 Orla (Órla)

Pronunciation: OR-lah
Meaning: Meaning “golden princess” in Irish, Orla was borne by medieval Irish royalty, including Brian Boru’s sister. A name steeped in nobility, it has retained its regal charm across centuries, making it a timeless choice in Ireland.

👑 Orlaith (Órlaith)

Pronunciation: OR-lah
Meaning: The older spelling of Orla, Orlaith was a popular name among Irish queens and noblewomen. It carries a strong association with wealth, power, and beauty, dating back to early Gaelic Ireland.

🌊 Oonagh (Úna)

Pronunciation: OO-nah
Meaning: An ancient Irish name meaning “lamb” or “unity,” Oonagh is linked to mythology as the wife of the legendary Fionn mac Cumhaill. It’s a name that exudes grace and softness, yet carries a deep cultural resonance.

✨ Oriana (Órína)

Pronunciation: or-ee-AH-nah
Meaning: Meaning “golden dawn,” Oriana is a radiant name with both Latin and Irish influences. It was famously used in poetry and legend, evoking images of sunrise and new beginnings.

👑 Orliana (Órlíana)

Pronunciation: or-lee-AH-nah
Meaning: A regal-sounding name likely derived from Orla (“golden princess”) with a lyrical twist. Orliana has an elegant, sophisticated feel, making it a modern evolution of classic Irish royal names.

🔥 Orlitha (Órlítha)

Pronunciation: or-LEE-thah
Meaning: A possible variation of Orla, meaning “golden flame” or “radiance.” Orlitha evokes images of warmth and brilliance, making it a striking alternative for those who love classic Irish names with a fiery twist.

🏛️ Olythia (Ólýthía)

Pronunciation: oh-LITH-ee-ah
Meaning: A variant of Olithia, Olythia has a stately and historical feel. It brings to mind ancient places of wisdom and culture, making it a distinctive and poetic name.

🌞 Orliana (Órlíana)

Pronunciation: or-lee-AH-nah
Meaning: A second appearance of Orliana—its golden, noble essence remains timeless. Whether inspired by Orla or reinvented with a unique twist, it shines as an elegant and rare choice.

💎 Ophiria (Ófhíría)

Pronunciation: oh-FEER-ee-ah
Meaning: A name linked to the biblical land of Ophir, known for its vast wealth and gold. Ophiria symbolizes prosperity and mystery, making it a luxurious yet uncommon name in Ireland.

Irish Boys First Names that Start with O

There are some classic names that start with O for boys, and lots of them are Irish twists on conventional names. Osgar is a good example, which is the Irish version of Oscar.

⭐ Our Favourite: Oisín (Oisín)

Pronunciation: UH-sheen
First Used: Early Irish mythology, Fenian Cycle
Meaning: Oisín means “little deer” and is one of the most famous names in Irish mythology. He was the son of the legendary warrior Fionn Mac Cumhaill and a great poet-warrior of the Fianna. His tale of love, heroism, and his journey to Tír na nÓg (the Land of Eternal Youth) is one of Ireland’s most cherished legends.
Why It’s Our Favourite: Oisín is a name that perfectly embodies Irish mythology—full of adventure, poetry, and mystery. It’s deeply rooted in Gaelic storytelling, yet still popular today. The name carries a strong yet lyrical quality, making it one of the most timeless and uniquely Irish choices.

🏹 Oliver (Oilibhéar)

Pronunciation: AHL-ih-ver
Meaning: Of Latin origin, Oliver means “olive tree,” symbolizing peace and fruitfulness. The Irish form, Oilibhéar, was influenced by Norman settlers. The name gained popularity through Oliver Cromwell and Charles Dickens’ Oliver Twist, though its roots in Ireland predate these figures.

🐺 Oscar (Osgar)

Pronunciation: OSS-kar
Meaning: Meaning “deer lover” or “friend of the deer,” Oscar comes from Irish mythology, as the name of a warrior in the Fenian Cycle, grandson of Fionn Mac Cumhaill. The name gained international fame through the legendary writer Oscar Wilde.

🛡️ Owen (Eoghan)

Pronunciation: OH-en
Meaning: A name of both Irish and Welsh origins, Eoghan means “born of the yew tree,” a symbol of resilience and longevity. It was borne by many ancient Irish kings and warriors, including Eoghan, son of Niall of the Nine Hostages.

🎵 Oran (Órán)

Pronunciation: OR-an
Meaning: Derived from ór, meaning “gold,” Oran can be translated as “little golden one.” It is also associated with Saint Oran, who founded a monastery on Iona. The name is linked to music and poetry, as órán means “song” in Irish.

🍀 Odhran (Odhrán)

Pronunciation: OHR-awn
Meaning: Meaning “little dark one,” Odhran was the name of several early Irish saints, including a companion of Saint Columba. It has ancient roots, tied to the mystical and monastic history of Ireland.

🌿 Oisin (Oisín)

Pronunciation: UH-sheen
Meaning: Meaning “little deer,” Oisín was the legendary son of Fionn Mac Cumhaill and the greatest poet-warrior of the Fianna. His mythical journey to Tír na nÓg (the Land of Eternal Youth) remains one of the most famous Irish legends.

📖 Odran (Odhrán)

Pronunciation: OHR-awn
Meaning: Another form of Odhran, Odran shares the meaning “little dark one.” It was borne by an early Irish saint, known as the first Christian martyr of Scotland. His name is tied to sacred burial sites and monastic lore.

🏹 Orton (Órtón)

Pronunciation: OR-tun
Meaning: Meaning “from the town by the shore,” Orton has Old English roots but fits well within Irish geography-based surnames. It mirrors the Gaelic tradition of names tied to land and place, making it an intriguing choice for those with Irish heritage.

🌿 Osian (Oisín)

Pronunciation: OH-shan
Meaning: A Welsh variant of Oisín, meaning “little deer,” Osian carries the same legendary weight as its Irish counterpart. In Wales, it is associated with the poet Osian Ellis, echoing the Irish warrior-poet Oisín of the Fenian Cycle.

🏰 Ormond (Órmónd)

Pronunciation: OR-mund
Meaning: Meaning “descendant of the high chieftain,” Ormond has strong Irish roots, notably in the Butlers of Ormond, an influential Anglo-Irish noble family. It is also linked to the province of Ormond (now part of Tipperary and Kilkenny).

🌊 Orren (Órren)

Pronunciation: OR-en
Meaning: A name of Gaelic origin meaning “little green one” or “dweller by the river,” Orren is closely tied to nature and the lush Irish landscape. It has an old-world charm while remaining easy to pronounce.

🌠 Oryan (Óríán)

Pronunciation: OR-ee-an
Meaning: A modern twist on Oran and Ryan, Oryan blends Gaelic and celestial influences. It echoes Orion, the hunter constellation, but also connects to the Irish word ór (gold), symbolizing brightness and strength.

🍀 Oweney (Eoghaní)

Pronunciation: OH-nee
Meaning: A diminutive of Eoghan, Oweney means “born of the yew tree.” This ancient Irish name was borne by many chieftains and warriors, symbolizing endurance and leadership, as the yew tree was revered in Celtic traditions.

🦌 Oskar (Osgar)

Pronunciation: OSS-kar
Meaning: Meaning “deer lover” or “friend of the deer,” Oskar is rooted in Norse and Irish traditions. The legendary Oscar of Irish mythology was the grandson of Fionn Mac Cumhaill and a great warrior of the Fianna.

🔥 Osmir (Ósmír)

Pronunciation: OZ-meer
Meaning: A unique name possibly derived from Old Norse, meaning “divine peace” or “renowned strength.” It carries echoes of Viking influence in medieval Ireland and would fit alongside Gaelic warrior names.

📜 Ockley (Óclaí)

Pronunciation: OCK-lee
Meaning: Meaning “oak meadow,” Ockley originates from Old English but fits within the Irish tradition of nature-based names. The oak tree was sacred to the Celts, symbolizing endurance and wisdom, making this a fitting choice.

We hope you found our list helpful and that it inspired you. We’d love for you to explore some of our other names and their meanings in Ireland.