extrametrical

[ ek-struh-me-tri-kuh l ]
/ ˌɛk strəˈmɛ trɪ kəl /

adjective Prosody.

containing one or more syllables in addition to those required by the meter: an extrametrical line.

Origin of extrametrical

First recorded in 1860–65; extra- + metrical
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019