D defs.my
Entry 1 sense Webster, 1913

ammonia

/(ăm*mō"nĭ*ȧ)/ · am·mo·ni·a · IPA /əˈmoʊn.jə/
01 n. A gaseous compound of hydrogen and nitrogen, NH3, with a pungent smell and taste: -- often called volatile alkali, and spirits of hartshorn…
  1. 1.
    A gaseous compound of hydrogen and nitrogen, NH3, with a pungent smell and taste: -- often called volatile alkali, and spirits of hartshorn. It is very soluble in water, forming a moderately alkaline solution, and is used in aqueous solution as a household cleaning agent, such as for cleaning grease from glass.(Chem.) Also: volatile alkali, spirits of hartshorn