| Name | Origins | Meaning |
| | | |
| Seamus | Irish Gaelic | Seamus means the supplanter. |
| Sean | Irish Gaelic | Sean meaning it's : God is gracious. |
| Seanan | Irish Gaelic | Seanan means old and wise. |
| Senan | Irish Gaelic | Senan means wise and inteligent. |
| Shamus | Irish Gaelic | Shamus meaning it's : the supplanter. |
| Shanahan | Irish Gaelic | Shanahan meaning it's : the wise one. |
| Shanley | Irish Gaelic | Shanley meaning it's : hero. |
| Shannon | Irish | Shannon it's a river name.It's a unique baby boy name and also a unique baby girl name. |
| Shaughan | Irish Gaelic | It means: God is gracious. |
| Shaun | Irish Gaelic | It means : God is gracious. |
| Shay | Irish Gaelic | Shay means statement.It's a unique baby boy name and also a unique baby girl name. |
| Shea | Irish | Shea means stately. |
| Sheehan | Irish Gaelic | Sheehan meaning it's peaceful. |
| Sheridan | Irish Gaelic | Sheridan means the wild one.It's a unique baby boy name and also a unique baby girl name. |
| Sheridon | Irish | Sheridon meaning it's : wild. |
| Skelly | Irish Gaelic | Skelly means : story teller. |
| Slevin | Irish Gaelic | Slevin meaning it's : mountain climber. |
| Sloan | Irish Gaelic | Sloan means warrior. |
| Stiofan | Irish Gaelic | Stiofan it's the Irish Gaelic form of Stephen. |
| Sullivan | Irish Gaelic | Sullivan meaning it's : black-eyed. |
| Sweeney | Irish Gaelic | Sweeney it's a hero name. |
| Tad | Irish Gaelic | Tad it's a poet name. |
| Tara | Irish Gaelic/Sanskrit | Tara meaning it's : star.It's a unique baby boy name and also a unique baby girl name. |
| Teague | Irish Gaelic | Teague it's a poet name. |
| Tiernan | Irish Gaelic | It means lord. |
| Tierney | Irish Gaelic | Tierney meaning it's : the son of the lord.It's a unique baby boy name and also a unique baby girl name. |
| Tomas | Irish Gaelic | Tomas meaning it's : twin. |
| Tormey | Irish Gaelic | Tormey means thunder spirit. |
| Tyrone | Irish | A county name,in Ireland. |
| Ultan | Irish | Ultan meaning it's: nice |