what does the file .fcpbundle mean?

In what context? From which version of FCPX?

If you don't have FCPX it doesn't really matter, you can't do anything with it.

.FCPBUNDLEFile Extension

File TypeFinal Cut Pro Library

What is an FCPBUNDLE file?

Library created and used by Final Cut Pro X (FCPX), a professional video editor; contains files that make up a library in FCPX, which includes a .FLEXOLIBRARY file, .FCPEVENT files describing events, and a .PLIST file that contains backup metadata.

More Information

The FCPBUNDLE file is located in the following directory:
MacHD/Library/Users/[username]/Movies/Final Cut Backups

This file IS a library and by default will contain your media, so yes.