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Webster 1913 Edition

Noun.

A temporary substitute for a bed, as one made on the floor or on chairs; – perhaps originally from the shaking down of straw for this purpose.

Sir W. Scott.

See also: shake down and shake-down

shakedown ‎(plural shakedowns)

(slang) Extortion, especially through blackmail
What is this, a shakedown?
(slang) A thorough search; a frisk
A trial or test period, especially of a ship or aircraft
An improvised bed.
- 1915, W.S. Maugham, "Of Human Bondage":
  "You'd better lie down for a bit. I expect you're about done up." -- "There's nowhere for me to lie down, sir," he answered, and there was in his voice a humbleness which was very distressing. -- "Don't you know anyone in the house who'll give you a shakedown?" -- "No, sir."

extortion

a thorough search

trial or test period

an improvised bed

shakedown

that tests the performance