hmm my turn to cut and paste
There are several theories about the origin of this common term for a familiar article of sanitary furniture. The first, and most popular, is that it is derived from the cry of 'gardyloo' (from the French regardez l'eau 'watch out for the water'😉 which was shouted by medieval servants as they emptied the chamber-pots out of the upstair windows into the street. This is historically problematic, since by the time the term 'loo' is recorded, the expression 'gardyloo' was long obsolete. A second theory is that the word derives from a polite use of the French term le lieu ('the place'😉 as a euphemism. Unfortunately, documentary evidence to support this idea is lacking. A third theory, favoured by many, refers to the trade name 'Waterloo', which appeared prominently displayed on the iron cisterns in many British outhouses during the early 20th century. This is more credible in terms of dates, but corroborating evidence is still frustratingly hard to find. Various other picturesque heories also circulate, involving references to doors numbered '00' or people called 'Looe'.
good old google tongue
blunt its true though.
u want more it is dropping from birds / bats it is rich phosphates and nitrates and can therefore be used as fertilizer. it comes from the Peruvian word huano.
but more importantly they are a great German band