[shake down] {v. phr.}
1. To cause to fall by shaking.
* /He shook some pears down from the free./
2. {informal} To test, practice, get running smoothly (a ship or ship's crew).
* /The captain shook down his new ship on a voyage to the Mediterranean Sea./
3. {slang} To get money from by threats.
* /The gangsters shook the store owner down every month./