from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A region of the upper atmosphere, between about 15 and 30 kilometers (10 and 20 miles) in altitude, containing a relatively high concentration of ozone that absorbs solar ultraviolet radiation in a wavelength range not screened by other atmospheric components. Also called ozonosphere.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A region of the stratosphere, between 15 and 30 kilometres in altitude, containing a relatively high concentration of ozone; it absorbs most solar ultraviolet radiation
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a layer in the stratosphere (at approximately 20 miles) that contains a concentration of ozone sufficient to block most ultraviolet radiation from the sun
Sorry, no etymologies found.