1. To move around in some amount or body of water in a playful, frenetic manner, causing lots of splashes in the process. Don't splash about too much in the bath, kids. I don't want the floor getting all wet. I used to love going to the pool as a kid and splashing about for the whole day.

2. To slosh around inside of something. The soup splashed about in the large serving bowl as the waiter wheeled it around the dining room. I drank too much water just before the run. Now I can feel it splashing about in my belly with every step I take!

3. To cause some liquid to slosh around in or out of something. In this usage, a noun or pronoun is used between "splash" and "about." Be careful not to splash the wine about as you carry those glasses to the table. I poured some water into the urn and splashed it about to rinse dust out.