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octosyllable

[ok-tuh-sil-uh-buh l]
noun
  1. a word or line of verse of eight syllables.

Origin of octosyllable

1765–75; part translation of Late Latin octōsyllabus; see octosyllabic, syllable
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for octosyllable

octosyllable

noun
  1. a line of verse composed of eight syllables
  2. a word of eight syllables
Derived Formsoctosyllabic (ˌɒktəsɪˈlæbɪk), adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012