say it: pah-lee-si-LAB-ik
polysyllabic is an adjective meaning "having or characterized by words of more than three syllables". It carries 2 recorded senses.
having or characterized by words of more than three syllables
(of words) long and ponderous; having many syllables
“sesquipedalian technical terms”
Definitions, synonyms and semantic relations for polysyllabic come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.