/ Dictionary / Index D decasyllable: Meaning and Definition of Find definitions for: dec•a•syl•la•ble Pronunciation: (dek'u-sil"u-bul), [key] — n. a word or line of verse of ten syllables. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: decasyllable (Thesaurus) decasyllabic decathect Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language