1. To shake something in order to mix up or loosen its contents. A noun or pronoun can be used between "shake" and "up." Make sure you shake up the carton of juice before you pour it out. It's easier to pour the ketchup if you shake the bottle up first.

2. To forcefully or drastically reorganize or rearrange something, as a group or organization. A noun or pronoun can be used between "shake" and "up." After the merger, the upper management of the company was completely shaken up. The scandal has really shaken things up within the department, with several members resigning or being fired.

3. To do something different from one's normal routine in order to make things feel new or interesting. A noun or pronoun can be used between "shake" and "up." I'm tired of getting Chinese food—let's shake things up and try that new Polynesian restaurant. It's important to shake up your day-to-day routine, or you may end up in a rut.

4. To make someone very upset; to frighten or shock someone. A noun or pronoun can be used between "shake" and "up." It seems like the car accident shook her up pretty badly. I was shaken up for most of the day after hearing about my grandfather's death.