Dictionary
ni'trogen tetrox'ide
Chem.
a poisonous compound, N
2O
4, occurring as a colorless, water-soluble solid or liquid, dissociating into NO
2: used chiefly as an oxidizer, esp. in rocket fuels, as a nitrating agent, and as an intermediate in the manufacture of nitric acid.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.