The Meaning of Life, the Universe, and Everything.
Yes, it's 100% Possible, this is what you have to do:
Make sure your server isn't running
1. Find the folder of the world you'd like to take for example Epic World.
2. Copy the folder, and paste it into the your server folder
3. Do not delete the world you already have, or take it it out, instead, go into the server.properties, and edit the world name to whatever it is, in this case, it would be Epic World.
4. Once you've done that, start up your server, and enjoy!