Webster's Revised Unabridged Dictionary · 1913

Amentaceous

Amentaceous ({not transcribed}) , adjective

[Late Latin amentaceus.]

(a)
(Botany) Resembling, or consisting of, an ament or aments; as, the chestnut has an amentaceous inflorescence.
(b)
(Botany) Bearing aments; having flowers arranged in aments; as, amentaceous plants.