| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Alastar | - | Irish | ||
| AlastrÍOna | al-as-TREE-na | Irish | ||
| Alby | - | Irish | ||
| Amhlaoibh | - | Irish | ||
| Angus | ANG-gəs | Scottish, Irish, English | ||
| AnraÍ | - | Irish | ||
| Aodh | EE, AY | Irish, Scottish, Irish Mythology | ||
| AodhÁN | - | Irish, Scottish, Irish Mythology | ||
| AodhagÁN | - | Irish, Scottish | ||
| AoibhÍN | EE-veen | Irish | ||
| Aoibhe | EE-va | Irish | ||
| Aoibheann | EE-van | Irish | ||
| Aoife | EE-fa | Irish, Irish Mythology | ||
| Aonghus | - | Irish, Scottish, Irish Mythology | ||
| Aran (1) | - | Irish |