Word Study
trisyllabical
CIDE DICTIONARY
trisyllabical, a. [L. trisyllabus, Gr. ; (see Tri-) + a syllable: cf. F. trissyllabique.].
Of or pertaining to a trisyllable; consisting of three syllables; as, “syllable” is a trisyllabic word. [1913 Webster]
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