- any of a genus (Hemerocallis) of plants of the lily family, with showy, trumpet-shaped flowers, usually opening for a single day
- plantain lily
See day lily in American Heritage Dictionary 4
or day·lil·y noun
Any of several perennial Eurasian herbs of the genus Hemerocallis in the lily family, having often grasslike leaves and yellow, orange, or purplish lilylike flowers. Also called hemerocallis.
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