| Achaicus | Man | Greek Names |
| Achava | Unisex | Hebrew Names |
| Achelle | Woman | American Names |
| Achelous | Man | Greek Names |
| Acheron | Man | Greek Names |
| Achille | Man | French Names |
| Achilles | Man | Greek Names |
| Achim | Man | Hebrew Names |
| Achsa | Woman | Hebrew Names |
| Acoose | Man | Native American - Ojibwa Names |
| Acosta | Unisex | Spanish Names |
| Acotas | Unisex | Native American - Blackfoot Names |
| Acsah | Woman | Hebrew Names |
| Acton | Man | English Names |
| Ada | Woman | German Names |
| Adabella | Woman | Spanish Names |
| Adagio | Man | Italian Names |
| Adah | Woman | Hebrew Names |
| Adahy | Man | Native American - Cherokee Names |
| Adair | Unisex | English Names |