| Archytas | Archytas |
| Archytas de Tarente | Archytas |
| Arché | Arche |
| Archéen | Archean |
| archégone | sporangium |
| Archélaos | Archelaus I of Macedon |
| Archélaos de Cappadoce | Archelaus of Cappadocia |
| Archéoastronomie | Archaeoastronomy |
| Archéocyathidés | Archaeocyatha |
| archéologie | archaeology |
| Archéologie biblique | Biblical archaeology |
| Archéologie expérimentale | Experimental archaeology |
| Archéologie industrielle | Industrial archaeology |
| archéologique | archaeological |
| archéologue | archaeologist |
| Archéosophie | Archeosophy |
| Archéozoologie | Zooarchaeology |
| Archéparchie catholique ukrainienne de Winnipeg | Ukrainian Catholic Archeparchy of Winnipeg |
| archétype | archetype |
| Arcins | Arsenic |
| Arcis-sur-Aube | Arcis-sur-Aube |
| ARCnet | ARCNET |
| Arcologie | Arcology |
| Arconciel | Arconciel |
| Arcore | Arcore |
| Arctica islandica | Arctica islandica |
| Arctiidae | Arctiidae |
| Arctiinae | Arctiinae |
| Arctinos de Milet | Arctinus of Miletus |
| Arctique | Arctic |
| Arctocebus | Angwantibo |
| Arctocephalus | Arctocephalus |
| Arctocephalus galapagoensis | Galapagos Fur Seal |
| Arctocephalus philippii | Juan Fernandez Fur Seal |
| Arctogalidia trivirgata | Small-toothed Palm Civet |
| Arctotheca | Arctotheca calendula |
| Arctotis | Arctotis |
| Arcturus | Arcturus |
| Arcueil | Arcueil |
| Arcul de Triumf | Arcul de Triumf |
| Arcésilas de Pitane | Arcesilaus |
| Ard ri Érenn | High King of Ireland |
| Arda | Arda |
| Ardabil | Ardabil |
| Ardachir III | Ardashir III |
| Ardachîr | Ardeshir |
| Ardachîr Ier | Ardashir I |
| Ardachîr II | Ardashir II |
| Ardahan | Ardahan Province |
| Ardalan | Ardalan |
| Ardaric | Ardaric |
