"lavatory," 1940, but perhaps 1922, probably from French lieux d'aisances, "lavatory," literally "place of ease," picked up by British servicemen in France during World War I. Or possibly a pun on Waterloo, based on water closet.
type of card game, 1670s, short for lanterloo (1660s), from French lanturelu, originally (1620s) the refrain of a popular comic song; according to French sources the refrain expresses a mocking refusal or an evasive answer and was formed on the older word for a type of song chorus, turelure; apparently a jingling reduplication of loure "bagpipe" (perhaps from Latin lura "bag, purse").
From its primary signification -- a kind of bagpipe inflated from the mouth -- the word 'loure' came to mean an old dance, in slower rhythm than the gigue, generally in 6-4 time. As this was danced to the nasal tones of the 'loure,' the term 'loure' was gradually applied to any passage meant to be played in the style of the old bagpipe airs. ["Grove's Dictionary of Music and Musicians," London, 1906]The refrain sometimes is met in English as turra-lurra.
A toilet •Chiefly British: everything you'd find in a powder room except the loo
[1940+; origin uncertain; perhaps fr Waterloo in proportionate analogy with water closet; perhaps fr the Edinburgh cry ''Gardyloo'' uttered when one threw the contents of the slopjar into the street; Mrs. Virginia Burton of Lynchburg, VA, suggests it may be a pronunciation of French lieu, ''place,'' in the phrase lieu d'aisance, ''toilet, lavatory'']
(also Loo) A lieutenant, esp of police: All lieutenants were called Loo (1990s+)