The familiar sanitation fixture used to dispose of human bodily waste is known by many names, one of them being “loo”, which is used predominantly in Britain. What’s interesting is that nobody knows its exact origin.
The first and most popular theory is that it is derived from the French expression regardez l’eau!, or “watch out for the water!” This was allegedly uttered by servants when they emptied chamber pots from upstairs windows into the filthy city streets below. However, this etymology is rejected by most modern experts since the expression had gone out of use long before the first recorded use of the word “loo”.
An alternative theory is also linked to a French expression, le lieu, or “the place”. This word was allegedly used as a polite euphemism for a toilet. However, there is little documentary evidence to support this.
Yet another French word that might point to the origin of “loo” is bourdalou, or portable night pots. Yet there is absolutely no written document that would link the two words.
A fourth theory links it to the trade name “Waterloo”, which was prominently displayed on many British cisterns in the early 20th century. This theory is the most credible in term of dates, but again there is little direct evidence.
Whatever the origin of the word, its oldest verifiable usage appears only in James Joyce’s Ulysses (1922), who indeed links it to the name “Waterloo”. Until more written documents containing the word are found, we will be left guessing as to the true origin of the word.