| Subject | English | Portuguese |
| gen. | Arctic area | zona ártica |
| life.sc., agric. | Arctic bramble | framboeseira-do-ártico (Rubus arcticus) |
| fish.farm. | Arctic char | salvelino-ártico (Salmo salvelinus, Salvelinus alpinus) |
| fish.farm. | Arctic charr | salvelino-ártico (Salmo salvelinus, Salvelinus alpinus, Salvelinus alpinus alpinus) |
| earth.sc. | Arctic Circle | círculo polar ártico |
| life.sc. | arctic climate | clima polar |
| fish.farm. | Arctic cod | bacalhau-polar (Boreogadus saida) |
| fish.farm. | Arctic cod | bacalhau-ártico (Eleginus navaga, Gadus navaga) |
| fish.farm. | Arctic cod | bacalhau-do-ártico (Eleginus navaga (Pallas), Gadus navaga) |
| environ. | Arctic Council | Conselho Ártico |
| environ. | Arctic ecosystem | ecossistema ártico |
| environ. | Arctic ecosystem | ecossistema árctico |
| fish.farm. | Arctic flounder | solha-ártica (Liopsetta glacialis) |
| fish.farm. | arctic flounder | solhao artico (Liopsetta glacialis) |
| life.sc., environ. | arctic fox | raposa-branca (Vulpes lagopus, Alopex lagopus) |
| earth.sc. | arctic front | frente ártica |
| life.sc. | arctic haze | bruma ártica |
| environ. | Arctic Ocean The smallest and most poorly studied of the oceans on earth. It covers an area of 14 million square km that is divided by three submarine ridges, i.e. the Alpha Ridge, the Lomonosov Ridge, and an extension of the mid-Atlantic ridge. It is also nearly landlocked, covered year-round by pack ice, and the third of its area is continental shelf | Oceano Árctico |
| environ. | Arctic Ocean | Oceano Ártico |
| econ. | Arctic Ocean | oceano Ártico |
| life.sc., agric. | Arctic raspberry | framboeseira-do-ártico (Rubus arcticus) |
| environ., nat.res. | Arctic redpoll | pintarroxo de Hornemann (Carduelis hornemanni) |
| nat.res. | arctic redpoll | pintarroxo-de-hornemann (Acanthis hornemanni, Carduelis hornemanni) |
| environ. | Arctic region | Região Ártica |
| environ. | Arctic region The northernmost area of the earth, centered on the North Pole, that includes the Arctic Ocean, the northern reaches of Canada, Alaska, Russia, Norway and most of Greenland, Iceland and Svalbard | Região Árctica |
| nat.res. | Arctic right whale | baleia-franca-boreal (Balaena mysticetus, Eubalaena mysticetus) |
| life.sc., environ., fish.farm. | Arctic right whale | baleia-franca-da-gronelândia (Balaena mysticetus) |
| life.sc., environ., fish.farm. | Arctic right whale | baleia-da-gronelândia (Balaena mysticetus) |
| nat.res. | Arctic root | rodiola (Rhodiola rosea) |
| industr., construct., chem. | arctic rubber | borracha anticristalizante |
| life.sc. | arctic sea smoke | nevoeiro de evaporação |
| life.sc., fish.farm. | Arctic skate | raia-do-ártico (Amblyraja hyperborea, Raja hyperborea) |
| nat.res. | Arctic skua | moleiro-parasítico (Stercorarius parasiticus) |
| nat.res. | Arctic skua | alcatorda-mergulheira (Stercorarius parasiticus) |
| nat.res. | arctic skua | moleiro-parasítico (Stercorarius parasiticus) |
| fish.farm. | Arctic smelt | eperlano-ártico (Osmerus dentex, Osmerus mordax dentex) |
| environ., nat.res. | Arctic tern | andorinha-do-mar-ártica (Sterna paradisaea) |
| nat.res. | arctic tern | andorinha-do-mar-ártica (Sterna macrura, Sterna paradisaea) |
| nat.sc. | arctic warbler | felosa-boreal (Phylloscopus borealis) |
| gen. | Arctic Window | Janela do Ártico |
| fin., polit. | Barents Euro-Arctic Council | Conselho Euro-Ártico do Mar de Barents |
| fin. | cooperation in the Euro-Arctic region | cooperação euroártica |
| nat.sc., environ., polit. | European Arctic stratospheric ozone experiment | experiência sobre o ozono estratosférico do Ártico europeu |
| nat.sc., environ., polit. | European Arctic stratospheric ozone experiment | Experiência Europeia sobre o Ozono Estratosférico Ártico |
| fish.farm. | North-East Arctic cod | bacalhau ártico-norueguês |
