The Collaborative International Dictionary
Polysyllabism
Polysyllabism \Pol`y*syl"la*bism\, n. The quality or state of being polysyllabic.
Wiktionary
polysyllabism
n. 1 (context linguistics English) The state or characteristic of having or using words containing multiple syllables, sometimes as a stage in the development of language. 2 polysyllabicism.