What do a.m. and p.m. stand for?


[trop-uh-sfeer, troh-puh-] /ˈtrɒp əˌsfɪər, ˈtroʊ pə-/
noun, Meteorology
the lowest layer of the atmosphere, 6 miles (10 km) high in some areas and as much as 12 miles (20 km) high in others, within which there is a steady drop in temperature with increasing altitude and within which nearly all cloud formations occur and weather conditions manifest themselves.
Origin of troposphere
1905-10; tropo- + sphere
Related forms
[trop-uh-sfer-ik, -sfeer-, troh-puh-] /ˌtrɒp əˈsfɛr ɪk, -ˈsfɪər-, ˌtroʊ pə-/ (Show IPA),
adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
Cite This Source
Examples from the web for troposphere
  • Thank you troposphere for so vividly reminding us how much disdain is still out there against the ideal of equality.
  • All agreed that the troposphere should be getting warmer.
  • If he does become a star, he may finally be able to get the backing to blast into the troposphere.
  • The troposphere warms, the stratosphere cools, which is what you would expect from an enhanced greenhouse effect.
  • The troposphere is warming while the stratosphere is cooling.
  • The signature of global warming is missing in the lower troposphere.
  • Therefore, global warming in the troposphere and stratospheric cooling due to ozone loss are parallel effects.
  • The stratosphere cooling while the troposphere warms.
  • The stratosphere cooling while the troposphere warms c.
  • The stratosphere sits on top of the troposphere, the lowest, densest layer of the atmosphere.
British Dictionary definitions for troposphere


the lowest atmospheric layer, about 18 kilometres (11 miles) thick at the equator to about 6 km (4 miles) at the Poles, in which air temperature decreases normally with height at about 6.5°C per km
Derived Forms
tropospheric (ˌtrɒpəˈsfɛrɪk) adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for troposphere

1914, from French troposphère, literally "sphere of change," coined by French meteorologist Philippe Teisserenc de Bort (1855-1913) from Greek tropos "a turn, change" (see trope) + sphaira "sphere" (see sphere).

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
troposphere in Science
  (trō'pə-sfîr', trŏp'ə-)   
The lowest and densest region of the Earth's atmosphere, extending from the Earth's surface to the tropopause. The troposphere is characterized by temperatures that decrease with increasing altitude. At the top of this region, temperatures are close to -55°C (-67°F). The weather, major wind systems, and cloud formations occur mostly in the troposphere. See also exosphere, mesosphere, stratosphere, thermosphere., See illustration at atmosphere.

The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
troposphere in Culture
troposphere [(troh-puh-sfeer, trop-uh-sfeer)]

The lowest layer of the atmosphere of the Earth, extending from ground level to an altitude of seven to ten miles.

The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
Cite This Source

Word of the Day

Difficulty index for troposphere

Few English speakers likely know this word

Word Value for troposphere

Scrabble Words With Friends

Nearby words for troposphere