TED-ED: Mysteries of vernacular: Keister - Jessica Oreck and Rachael Teel

The video explores the word 'keister', which today refers to a person's buttocks. Its etymology traces back to the Proto-Indo-European 'kista', meaning a woven container, influencing words like the Greek 'kiste' and Latin 'cista'. In Proto-Germanic, 'kista' described a box-like container, leading to the English 'chest'. The term 'keister' was used in 19th-century crime jargon to mean a burglar's toolkit and later a safe. Theories suggest its connection to buttocks comes from pick-pocket slang for a rear trouser pocket.

How did the meaning of 'keister' evolve in the context of burglary in the late 1800s?

Discuss the theories regarding 'keister's' association with buttocks.