Keister,

a person's buttocks.

Though the modern meaning of keister

refers somewhat indecorously

to a person's behind,

the word's history does not begin with the rear end.

Instead, it can be traced back

to the Proto-Indo-European kista,

which described a woven container.

Kista influenced the creation of words

like the Greek kiste,

meaning basket or box,

and later, the Latin cista,

which meant box or chest.

In proto-Germanic, a sturdy, box-like container

was described by the word kista,

which eventually gave us chest in English.

For every locked chest,

there is both a key and a lock pick,

and the history of keister

draws us into this world of petty crime

and speculative etymology.

Keister may have come from the British dialect kist,

which was the northern form of chest.

In the underworld jargon of the late 1800s,

it referred to a burgler's tool kit that can be locked,

and by the early 20th century,

it meant safe or strong box.

Numerous theories about keister's connection

to the buttocks abound,

one being, that is courtesy of the slang sense,

used by pick-pockets to describe

the treasure of a rear trouser pocket.

Unfortunately, what isn't safe in your kist

may not be safe near your keister either.