n. any oxide containing a single oxygen atom in each molecule or formula unit
the GNU version of the Collaborative International Dictionary of English
n. An oxide containing one atom of oxygen in each molecule.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. an oxide containing just one atom of oxygen in the molecule
Word Usage
"I dunno that that's so -- carbon monoxide is almost exactly the same density as air, and the National Fire Protection Association code is fine with putting a detector on the ceiling so long as it's someplace you can hear it."