The Collaborative International Dictionary
NH4
Ammonium \Am*mo"ni*um\, n. [See Ammonia.] (Chem.) A compound radical, NH4, having the chemical relations of a strongly basic element like the alkali metals.
Wikipedia
NH4
NH4 or NH 4 or NH-4 may refer to:
- Ammonium, the cation NH in chemistry
- National Highway 4 (India), a major National Highway in western and southern India
- New Hampshire Route 4, a short state highway located in eastern Strafford County, New Hampshire, United States