ammoniac \am*mo"ni*ac\ ([a^]m*m[=o]"n[i^]*[a^]k), Ammoniacal
\Am`mo*ni"a*cal\ ([a^]m`m[-o]*n[imac]"[.a]*kal), a.
Of, pertaining, or containing ammonia, or possessing its
properties; as, an ammoniac salt; ammoniacal gas.
[1913 Webster]
{Ammoniacal engine}, an engine in which the vapor of ammonia
is used as the motive force.
{Sal ammoniac} [L. sal ammoniacus], the salt usually called
{chloride of ammonium}, and formerly {muriate of ammonia}.
[1913 Webster] Gum ammoniac