Amonia

Ammonia is a compound with the formula NH₃. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of the planet as a precursor to foodstuffs and fertilizers. Ammonia, either directly or indirectly, is a building block for the synthesis of most pharmaceuticals. Although it is in wide use, ammonia is caustic and hazardous.
See more at Wikipedia.org...

n. ammonia, colorless soluble gas (Chemistry)

/amoniak/ ammonia