Lau means: A verb in Polari, the British gay subculture cant language, meaning to put down or place something. Polari had a distinct vocabulary drawn from Romani, Italian, and other sources, and was used as a. The word is mostly archaic or historical; you will only encounter it in old texts, period drama, or school history rather than current teen conversation. It has drug-related associations; worth a calm conversation about which side of the topic your teen is on. As a place or proper-name reference it is purely descriptive.