from The American Heritage® Dictionary of the English Language, 4th Edition
- The parallel of latitude approximately 66°33ʹ north. It forms the boundary between the North Temperate and North Frigid zones.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- proper n. The line which marks approximately the southernmost place in the Northern Hemisphere where the sun does not set on the summer solstice and does not rise on the winter solstice.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a line of latitude near but to the south of the north pole; it marks the northernmost point at which the sun is visible on the northern winter solstice and the southernmost point at which the midnight sun can be seen on the northern summer solstice
Sorry, no etymologies found.
And, crucial for polar research, the ice-strengthened hull allowed her to plough through the shattered sea ice which choked the coastal waters north of the Arctic Circle even in early summer.
For half an hour since their refuelling stop at Reykjavik they had been out of sight of land, but after passing over the Arctic Circle the sea had become increasingly speckled with white.