The Bedford Glossary of Critical and Literary Terms - Ross Murfin 2018
Feminine ending (light ending)
Feminine ending (light ending): A line of verse ending with an extra, unstressed syllable is said to have a feminine ending. This extrametrical syllable, which usually concludes an iambic or anapestic line, often provides rhythmical variety and movement.
EXAMPLE: The following humorous, half-rhymed, generally anapestic lines in A Fable for Critics (1848), James Russell Lowell’s long poem about the mid-nineteenth-century American artistic scene, have feminine endings:
Why̆, thĕre’s scárce│ly̆ ă húd│dlĕ ŏf lóg-│hŭts ănd shán│tiĕs
Thăt hăs│nŏt brŏught fórth│ı̇̆ts ŏwn Mі́l│tŏns ănd Dán│tĕs;
Ĭ my̆sélf│knŏw tĕn Bý│rŏns, ŏne Cóle│rı̇̆dge, thrĕe Shél│ley̆s,
Two Raphaels, six Titians, (I think) one Apelles,
Leonardos and Rubenses plenty as lichens,
One (but that one is plenty) American Dickens… .