Extrametrical definitions

extrametrical

in prosody, exceeding the usual or prescribed number of syllables in a given metre. Also, in reference to a syllable or syllables not counted in ...
Found on http://www.britannica.com/eb/a-z/e/62

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extrametrical

containing one or more syllables in addition to those required by the meter: an extrametrical line.
Found on https://www.infoplease.com/dictionary/extrametrical

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