Word Study
ammoniacal
CIDE DICTIONARY
ammoniacal, a.
Of, pertaining, or containing ammonia, or possessing its properties; as, an ammoniac salt; ammoniacal gas. [1913 Webster]
OXFORD DICTIONARY
ammoniacal, adj. of, relating to, or containing ammonia or sal ammoniac.
Etymology
ME ammoniac f. OF (arm-, amm-) f. L f. Gk ammoniakos of Ammon (cf. SAL AMMONIAC) + -AL
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