| Liam | Irish | Short form of Uilliam, the Irish co.. |  |  |
| Lile | Irish | Gaelic form of Lily, a borrowing of.. |  | |
| Lily | Irish | Taken from the name of the plant ha.. | | |
| Lisa | Irish | A short form of Elisabeth (God is m.. | | |
| Lochlainn | Irish | Popular name that originated from L.. | | |
| Logan | Irish | Transferred use of the surname, whi.. |  | |
| Loman | Irish | Derived from the diminutive form of.. |  | |
| Lorcan | Irish | Derived from the diminutive form of.. | | |
| Lorna | Irish | 19th-century coinage of English nov.. | | |
| Lorraine | Irish | Transferred use of the surname orig.. | | |
| Louise | Irish | Feminine form of Louis, which is .. | | |
| Lucan | Irish | A borrowing from the Latin, Lucan i.. | | |
| Lucas | Irish | Gaelic form of Lucas and Luke. See .. | | |
| Lucas | Irish | Gaelic form of Lucas and Luke. See .. | | |
| Lucius | Irish | A borrowing from the Latin, Lucius .. | | |
| Lucy | Irish | Feminine form of Lucius, which is.. | | |
| Lughaidh | Irish | Ancient name of uncertain derivatio.. | | |
| Luighseach | Irish | Feminine form of Lughaidh, an old .. | | |
| Luke | Irish | Middle English and Anglo-French for.. | | |
| Lunn | Irish | Meaning "warlike." | | |
| Lynch | Irish | Meaning "mariner." | | |
| Lysagh | Irish | Anglicized form of Laoighseach and .. | | |
| Mackenzie | Irish | Meaning "daughter of the wise leade.. | | |
| Mada | Irish | Gaelic form of Maude (powerful in b.. | | |
| Madailein | Irish | Gaelic form of Madeline (of Magdala.. | | |
| Madeline | Irish | Irish cognate of Magdalene, which i.. | | |
| Maeleachlainn | Irish | Compound name meaning "servant of S.. | | |
| Maeve | Irish | Anglicized form of Meadhbh, a name .. | | |
| Magee | Irish | Meaning "son of Hugh." Usually a su.. | | |
| Maggie | Irish | Pet form of Margaret (a pearl). Mag.. | | |
| Maghnus | Irish | Gaelic form of Magnus (great). See .. | | |
| Magnus | Irish | A borrowing from the Latin, Magnus .. | | |
| Maguire | Irish | Transferred use of the surname, whi.. | | |
| Mahon | Irish | Anglicized form of Mathghamhain (a .. | | |
| Maille | Irish | Pet form of Maire. See MAlRE. Mai.. | | |
