late 14c., ammoniak, also armonyak, in reference to certain gums, earths or salts (sal ammoniac) used medicinally and held to have similar properties (see ammonia); from Old French ammoniac, armoniac, ultimately from Greek *ammoniakos, from the god-name Ammon (q.v.).
The gum (Latin guttae ammoniaci) came from a wild plant that grew across North Africa and Asia. The earth (Latin bolus armenicus) was so called because the substance was found in Armenia; hence the medieval forms were confused with words from Greek harmonia (gum ammoniac was used as a binding agent) or Armenia.
updated on September 20, 2022