| Archaea | Archaea |
| Archaeoastronomy | Arqueoastronomía |
| Archaeobatrachia | Archaeobatrachia |
| Archaeoceratops | Archaeoceratops |
| Archaeoceti | Archaeoceti |
| Archaeocyatha | Archaeocyatha |
| Archaeogastropoda | Archaeogastropoda |
| archaeological | arqueológico |
| Archaeological culture | Cultura |
| Archaeological industry | Industria |
| archaeological site | zona arqueológica |
| Archaeological theory | Historia y teoría de la Arqueología |
| archaeologist | arqueólogo |
| archaeology | arqueología |
| Archaeology and the Book of Mormon | Arqueología y el Libro de Mormón |
| Archaeology of Israel | Arqueología de Israel |
| Archaeology of the Americas | Prehistoria de América |
| Archaeopteryx | Archaeopteryx |
| Archaeornithomimus | Archaeornithomimus |
| Archaeothyris | Archaeothyris |
| Archaeplastida | Primoplantae |
| archaic | antiguo |
| Archaic Period | Período arcaico |
| Archaic period in Greece | Época Arcaica |
| Archaic period in the Americas | Periodo arcaico de América |
| archaism | arcaísmo |
| archangel | arcángel |
| Archangel class assault ship | Archangel |
| archbishop | arzobispo |
| Archbishop of Armagh | Arzobispo de Armagh |
| Archbishop of Canterbury | Arzobispo de Canterbury |
| Archbishop of Cologne | Arzobispado de Colonia |
| Archbishop of Westminster | Arquidiócesis de Westminster |
| archbishopric | arquidiócesis |
| Archbishopric of Cologne | Arzobispado de Colonia |
| Archbishopric of Salzburg | Arzobispado de Salzburgo |
| archdeacon | arcediano |
| archdiocese | arquidiócesis |
| Archdiocese of Cologne | Arzobispado de Colonia |
| Archdiocese of Ho Chi Minh city | Archdiocese del ciudad Ho Chi Minh |
| Archdiocese of Toledo | Archidiócesis de Toledo |
| archduchess | archiduquesa |
| Archduchess Maria Anna of Austria | Mariana de Austria |
| Archduchess Maria Josepha of Austria | María Josefa de Austria |
| Archduchess Marie Amalie of Austria | María Amelia de Austria |
| Archduchess Sophie of Austria | Sofía Federica de Austria |
| archduke | archiduque |
| Archduke Ernest of Austria | Ernesto de Austria |
| Archduke Ferdinand Charles of Austria | Fernando Carlos de Habsburgo-Médicis |
| Archduke Ferdinand of Austria-Este | Fernando Carlos de Habsburgo-Médicis |
| Archduke Franz Ferdinand of Austria | Francisco Fernando de Austria |
| Archduke Franz Karl of Austria | Francisco Carlos de Austria |
| Archduke Ludwig Viktor of Austria | Luis Víctor de Austria |
| Archduke Rainer of Austria | Rainiero de Austria |
| Arche | Arjé |
| Archean | Eón Arcaico |
| arched | arqueado |
| arched passageway | arcada |
| Archelaus I of Macedon | Arquelao I |
| Archelon | Archelon |
| archenemy | archienemigo |
| Archenland | Archenland |
| archeological | arqueológico |
| archeologist | arqueólogo |
| archeology | arqueología |
| Archeosophy | Arqueosofía |
| archer | arquero |
| Archer John Porter Martin | Archer John Porter Martin |
| archery | ballestería |
| Arches National Park | Parque Nacional Arches |
| archetypal | arquetípico |
| archetype | arquetipo |
| Archibald Hill | Archibald Vivian Hill |
| ArchiCAD | ArchiCAD |
| Archidamus II | Arquídamo II |
| Archidamus III | Arquídamo III |
| Archie Hahn | Archie Hahn |
| Archie search engine | Archie |
| archiepiscopal | arzobispal |
| Archilochus | Arquíloco |
| Archimedean screw | Tornillo de Arquímedes |
| Archimedean solid | Sólidos arquimedianos |
| Archimedean solids | Sólidos arquimedianos |
| Archimedean spiral | Espiral de Arquímedes |
| Archimedes | Arquímedes |
| Archimedes number | Número de Arquímedes |
| Archimedes Palimpsest | Palimpsesto de Arquímedes |
| Archipalego | Archipiélago |
| archipelago | archipiélago |
