| Autosom | autosome |
| autonom | autonomous self-governed |
| Autodrom | motor-racing circuit dodgems track bumper car dodgem |
| Autozoom | autozoom |
| autogam | autogamous |
| Mitosom | mitosome |
| Zytosom | cytosome |
| auto- | self- auto- |
| Autist | autist autistic person |
| Auto | car motor car auto order resolution writ |
| Autobombe | car bomb |
| Autobus | bus coach motorbus |
| Autocar | bus |
| Autochrom | autochrome |
| Autocue | autocue |
| Automat | vending machine |
| Autonomie | autonomy |
| Autopsie | autopsy |
| Autor | author literator |
| Autorin | author writer |