O-P
The abbreviations in the "category" column are: A=anglicization T= traditional name Tr= Irish translation of a non-Irish name M= modern creation P= place name L= last name, S= saint name.
| Name (gender) | Category | Pronunciation | Other Forms | Origin/Meaning |
|---|---|---|---|---|
| Odhrán (m) | T,S | UR awn | Oran, Odrán, Órán | sallow |
| Ógán (m) | T | OH gawn | Hogan | youth; lad |
| Oilithir (m) | T,S | ULL ih hir | Ailithir | pilgrim |
| Oilleóg (m) | T, S | ILL yoge | Oilléog | dim. of Oillil ("sprite; elf") |
| Oillill (m) | T, S | UHL yil | Aillill, Elias | sprite; elf |
| Oillín (m) | T | UHL yeen | Ellén, Aillén | little sprite; elf |
| Oisín (m) | T,S | USH een | Ossian, Oissíne | little deer |
| Olcán (m) | T | UL cawn | - | wolf |
| Ólchobhar (m) | T | OLE chur | Ólchobar | lover of drink |
| Onchú (m) | T, S | UN choo | - | fierce hound |
| Onóra (f) | Tr | uh NO ra | Annora, Nora | Honor (from Latin) |
| Oonagh (f) | A | OO na | Úna, Oona | possibly, "lamb" |
| Oran (m) | A,S | OR an | Odhrán | dun-colored |
| Orinthia (f) | M | or IN thee a | - | name invented by George Bernard Shaw |
| Orla (f) | A | OR la | Órfhlaith, Órlaith | golden princess |
| Órlaith (f) | T | OR la | Orla, Órla, Orfhlaith | golden princess |
| Órnait (f) | T,S | OR nit | Ornat, Orna, Odharnait, Odarnait | sallow |
| Orthanach (m) | T | UR han ach | - | potent in prayers or charms |
| Osán (m) | T, S | US awn | Ossán | little deer |
| Oscar (m) | A | OSS car | Osgar | deer lover |
| Osgar (m) | T | US gar | Oscar | deer lover |
| Osnait (f) | T, S | US nit | Ossnat | deer |
| Ossian (m) | A | OSH ee an | Oisín | deer, stag |
| Owen (m) | A,S | OH in | Eoin, Eoghan | an anglicization of either John - from Hebrew meaning "God is gracious", or of Eoghan, which is Irish meaning "yew-born" |
| Pádraig (m) | Tr,S | PAW drig, PO ric, PAW drik | Pádraic, Patrick | from Latin Patricius- "nobleman" |
| Pádraigín (usually f) | Tr | PAW drag een, POR ick een | Patricia | from Latin Patricius- "nobleman" |
| Páidín (m) | Tr | PAW deen, PAW djeen | Paudeen | diminutive of Pádraig |
| Parthalán (m) | Tr | PAR ha lawn | Bartholomew, Bartley | from Hebrew, "son of Talmai" |
| Patrick (m) | A,S | PAT rick | Pádraig, Pádraic | from Latin Patricius- "nobleman" |
| Peadar (m) | Tr | PAD ar | Peter | from Greek petros- "rock" |
| Piaras (m) | Tr | PEE a rus | Peter | from Greek petros- "rock" |
| Pierce/Pearse (m) | A/L | PEERS | Piaras | from Greek petros- "rock" |
| Pilib (m) | Tr | PIL ib | Philip | from Greek Philippos- "horse-lover" |
| Póilín (f) | Tr | PO aleen | Pauline, Pauleen | from Latin Paul (Fem. form)- small |
| Pól (m) | Tr | POLE | Paul | from Latin- "small" |
| Proinnséas (f) | Tr | PRUN shis | Frances | from Latin- "Frenchman" |
| Proinnsias (m) | Tr | PRUN shis | Francis | from Latin- "Frenchman" |