| Armée romaine | Roman army |
| Armée rouge | Red Army |
| Armée rouge japonaise | Japanese Red Army |
| Armée roumaine | Romanian Armed Forces |
| Armée russe | Armed Forces of the Russian Federation |
| Armée Républicaine Irlandaise | IRA |
| Armée républicaine irlandaise provisoire | Provisional Irish Republican Army |
| Armée révolutionnaire bretonne | Liberation Front of Brittany |
| Armée suisse | Military of Switzerland |
| Armée territoriale | Territorials |
| Armée tunisienne | Military of Tunisia |
| Armée Vlassov | Russian Liberation Army |
| Armée vénézuélienne | Military of Venezuela |
| Armée zapatiste de libération nationale | Zapatista Army of National Liberation |
| Armées blanches | White movement |
| Armées vertes | Green armies |
| Arménie | Armenia |
| Arménie occidentale | Western Armenia |
| Arménie russe | Armenians in the Russian Empire |
| arménien | Armenian |
| Arménien oriental | Eastern Armenian language |
| Arménienne | Armenian |
| Armérie maritime | Armeria maritima |
| ARN | RNA |
| Arn Anderson | Arn Anderson |
| ARN interférent | Small interfering RNA |
| ARN polymérase | RNA polymerase |
| Arnac-Pompadour | Arnac-Pompadour |
| Arnacher | Gear |
| Arnakuagsak | Arnakuagsak |
| Arnaldo Forlani | Arnaldo Forlani |
| Arnaldo Ochoa Sánchez | Arnaldo Ochoa |
| Arnaldo Tamayo Méndez | Arnaldo Tamayo Méndez |
| Arnapkapfaaluk | Arnapkapfaaluk |
| arnaque | swindle |
| arnaquer | defraud |
| Arnaquer qqun | Drum |
| arnaqueur | conman |
| arnaqueuse | con artist |
| Arnaud | Arnaud |
| Arnaud Amaury | Arnaud Amalric |
| Arnaud de Brescia | Arnold of Brescia |
| Arnaud de Cervole | Arnaud de Cervole |
| Arnaud de Toroge | Arnold of Torroja |
| Arnaud de Villeneuve | Arnaldus de Villa Nova |
| Arnaud di Pasquale | Arnaud di Pasquale |
| Arnaut Daniel | Arnaut Daniel |
| Arnay-le-Duc | Arnay-le-Duc |
| Arne Friedrich | Arne Friedrich |
| Arne Tiselius | Arne Tiselius |
| Arnex-sur-Nyon | Arnex-sur-Nyon |
| Arnex-sur-Orbe | Arnex-sur-Orbe |
| Arngrímur Jónsson | Arngrímur Jónsson |
| Arnhem | Arnhem |
| arni | water buffalo |
| arnica | arnica |
| Arnis | Eskrima |
| ARNm | RNA |
| Arno | Arno River |
| Arno Allan Penzias | Arno Allan Penzias |
| Arno Arthur Wachmann | Arno Arthur Wachmann |
| Arno Babadjanian | Arno Babajanian |
| Arno Breker | Arno Breker |
| Arnobe | Arnobius |
| Arnold Böcklin | Arnold Böcklin |
| Arnold Förster | Arnold Förster |
| Arnold Gehlen | Arnold Gehlen |
| Arnold Harberger | Arnold Harberger |
| Arnold Harris Matthew | Arnold Matthew |
| Arnold Janssen | Arnold Janssen |
| Arnold Koller | Arnold Koller |
| Arnold Paole | Arnold Paole |
| Arnold Rüütel | Arnold Rüütel |
| Arnold Schlick | Arnolt Schlick |
| Arnold Schwarzenegger | Arnold Schwarzenegger |
| Arnold Schönberg | Arnold Schoenberg |
| Arnold Sommerfeld | Arnold Sommerfeld |
| Arnold van Gennep | Arnold van Gennep |
| Arnold von Winkelried | Arnold von Winkelried |
| Arnoldo Iguaran | Arnoldo Iguarán |
| Arnoldo Mondadori Editore | Arnoldo Mondadori Editore |
| Arnolfo di Cambio | Arnolfo di Cambio |
| Arnolphe | Arnulf |
| Arnor | Arnor |
| Arnoud | Arnulf |
| Arnoul | Arnulf |
| Arnoul de Chocques | Arnulf of Chocques |
| Arnoul de Metz | Arnulf of Metz |
| Arnoul de Montgommery | Arnulf of Montgomery |
