Figurative of whiteness, fairness, purity. The Latin word has become the general word in languages across Europe: German lilie, Dutch lelie, Swedish lilja, French lis, Spanish lirio, Italian giglio, Polish lilija, Russian liliya. The French word is contracted from Latin lilius, a rare surviving nominative form in French. In Old French lilie (12c.) also existed. Related: Lilied; lilaceous.
The lily of the valley translates Latin lilium convallium (Vulgate), a literal rendition of the Hebrew term in Song of Solomon ii:1; in modern times the name was applied to a particular plant (Convallaria majalis) apparently first by 16c. German herbalists. Lily pad is from 1834, American English. For gild the lily see gilded.
Originally in Middle English this was the word for the disease itself (mid-13c., via Old French lepre); the shift in meaning to "person with leprosy" perhaps developed in Anglo-French, or is because the -er ending resembled an agent-noun affix. By mid-15c. other nouns for the disease were being coined (see leprosy). In English lepra also was an old name for psoriasis (late 14c.).
type of stalked echinoderm found in Paleozoic fossils and, living, at great depths in the sea, 1847, from Latinized form of Greek krinoeides "lily-like," from krinon "lily" (a foreign word of unknown origin) + -oeides "like" (see -oid). So called from their resemblance to a lily or tulip. The word is attested as an adjective in English, "lily-shaped," from 1836. Related: Crinoidal.