Gardyloo

Interjection

gardyloo

1. (Scotland, obsolete) Used by people in medieval Scotland to warn passers-by of waste about to be thrown from a window into the street below. The term was still in use as late as the 1930s and 1940s, when many people had no indoor toilets. 

Noun

gardyloo (plural gardyloos)

1. (Scotland, historical) A cry of “gardyloo”. 
2. An act of discarding waste or some other substance from a height.