| Atabeg | Atabeg |
| Atacama | Atacama Desert |
| Atacamite | Atacamite |
| Atacora | Atakora Department |
| Atahualpa | Atahualpa |
| Atahualpa Yupanqui | Atahualpa Yupanqui |
| Ataka | National Union Attack |
| Atakapa | Atakapa language |
| Atakpamé | Atakpamé |
| Atal Bihari Vajpayee | Atal Bihari Vajpayee |
| Atalante | Atalanta |
| ATAPI | ATAPI |
| Atapuerca | Atapuerca |
| Atari teenage riot | Atari Teenage Riot |
| atavique | atavistic |
| atavisme | atavism |
| Ataxie télangiectasie | Ataxia telangiectasia |
| Ataxite | Ataxite |
| Atbara | Atbarah River |
| ATC | ATC |
| ATC code A | ATC code A |
| ATC code B | ATC code B |
| ATC code C | ATC code C |
| ATC code D | ATC code D |
| ATC code G | ATC code G |
| ATC code H | ATC code H |
| ATC code J | ATC code J |
| ATC code L | ATC code L |
| ATC code M | ATC code M |
| ATC code N | ATC code N |
| ATC code P | ATC code P |
| ATC code R | ATC code R |
| ATC code S | ATC code S |
| ATC code V | ATC code V |
| Atchinsk | Achinsk |
| atchoum | sneeze |
| atchoum! | achoo |
| Atefah Rajabi Sahaaleh | Atefah Sahaaleh |
| Atelecyclus | Circular crab |
| Ateleopodiformes | Jellynose fish |
| atelier | workroom |
| atelier d'exploitation | sweatshop |
| atelier de bricolage | den |
| Atelier de construction mécanique | Engineering factory |
| atelier de décapage | pickling plant |
| atelier de misère | sweatshop |
| atelier de peinture | paint room |
| atelier de pressurage | sweatshop |
| atelier de reliure | bindery |
| Atelier de réparation | Fixery |
| Ateliers nationaux | National Workshops |
| Atelinae | Atelinae |
| Atelomycterus marmoratus | Coral catshark |
| Atelophryniscus chrysophorus | Atelophryniscus |
| Atelopus | Atelopus |
