Nouns

(n)shakedowninitial adjustments to improve the functioning or the efficiency and to bring to a more satisfactory state“the new industry's economic shakedown”
(n)shakedowna very thorough search of a person or a place“a shakedown by the police uncovered the drugs”
(n)shakedownextortion of money (as by blackmail)

Adjectives

(a)shakedownintended to test a new system under operating conditions and to familiarize the operators with the system“a shakedown cruise”