Yes, and this is true for a field of any type.
You can open File 1 and go to Manage | Database | Relationships. There, you can click the far bottom left button to add a new table occurrence "box" to your relationships graph. In the dialog that opens, you can select an option to "add FileMaker Data source". Use that option to find and select File 2. In the next dialog that opens, select the table that has the desired container field defined.
This adds an occurrence of this table from file 2 to file 1 and you can now reference this table occurrence in layouts, scripts, calculations, relationships, value lists just as though this table is actually part of file 1.
That is great, I am going to try that out. Thanks