Hemerocallis

Hem′e·ro·cal′lis (hĕm′ē·rō·kăl′lĭs or hē′mē·), n. [NL., fr. Gr. ἡμεροκαλλίς; ἡμέρα day + ? beauty.] (Bot.) A genus of plants, some species of which are cultivated for their beautiful flowers; day lily.