from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A poisonous brown gas, NO2, often found in smog and automobile exhaust fumes and synthesized for use as a nitrating agent, a catalyst, and an oxidizing agent.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. the binary compound NO2, a brownish gas that is a poisonous air pollutant; it exists in equilibrium with dinitrogen tetroxide.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a highly poisonous brown gas (NO2)
Sorry, no etymologies found.