Nitrous

Part of speech: adjective (a.)

1. Of, pertaining to, or containing, niter; of the quality of niter, or resembling it.

2. Of, pertaining to, or designating, any one of those compounds in which nitrogen has a relatively lower valence as contrasted with nitric compounds. Nitrous acid (Chem.), a hypothetical acid of nitrogen HNO2, not known in the free state, but forming a well known series of salts, viz., the nitrites. -- Nitrous oxide. See Laughing gas.