What does ammoniac mean?
Ammoniac is a gum-resin harvested from certain umbelliferous plants native to Central Asia, particularly species of the genus Dorema. When the stems are cut, they exude a milky juice that hardens into yellowish lumps with a characteristic acrid taste and strong odor. Known since antiquity and prized by Greek, Roman, and later European physicians, ammoniac was long used as an expectorant to relieve coughs and bronchial complaints, and it also appeared in plasters applied externally. In modern English the word survives mostly in historical, pharmaceutical, and specialist contexts, having been largely displaced by synthetic medicines. It should not be confused with ammonia, the familiar pungent gas used in cleaning products, though both names ultimately trace back to the Egyptian god Ammon, near whose temple the resin was once traded. Related forms include the adjective 'ammoniacal', which today more often refers to compounds containing ammonia.
nounA gum-resin obtained from the stems of certain Asian plants of the genus Dorema (formerly Ammoniacum), exuded as a milky fluid that hardens into lumps and is used in medicine chiefly as an expectorant.
- A gum-resin exuded by plants of the genus Dorema, used medicinally as an expectorant and in plasters.
"The apothecary measured out a portion of ammoniac to compound into a cough syrup."
"Old pharmacopoeias list ammoniac among the standard ingredients for treating chronic coughs."
"The chemist ground the amber lumps of ammoniac into powder before dissolving them."
Rarely pluralized; the substance is normally treated as a mass noun.
"The trade catalog listed several grades of ammoniacs from different regions."
This obscure medicinal gum takes its name from the Egyptian god Ammon — the same deity that gave us ammonia and even inspired the name of spiral-shelled ammonite fossils.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of ammoniac
The word ammoniac derives from Latin ammoniacum, borrowed from Greek ammōniakon, meaning 'of Ammon' — referring to the Egyptian deity Ammon, whose temple at the oasis of Siwa was a famed trading center for the resin. The same divine name underlies the related terms ammonia, ammonium, and ammonite, the last applied to fossilized spiral shells resembling the god's ram-horned iconography. The word entered English in the late Middle Ages through Latin scientific writing.
Related word forms
How ammoniac is actually used
Now largely historical or specialist vocabulary, found mainly in older medical texts, pharmacology, and discussions of traditional medicine. The adjective form 'ammoniacal' describes substances containing or relating to ammonia.
Easily confused with ammoniac
Ammonia is a pungent gas (NH₃) or its aqueous solution used as a cleaner, while ammoniac is a medicinal gum-resin from an Asian plant; they share only a distant etymological link to the Egyptian god Ammon.