If you select the Restricted option in the Attribute Mask section of the TM definition page, the attribute selection fields will appear, allowing you to select TM entry attributes that will be available when you edit TM entries. If you don't want specific TM Entry attributes to apply to a particular TM, you could use the attribute mask to prevent it from appearing.

For example, you might create TM entry attributes for selecting a department and product groups with which a particular TM entry can be associated:

When you edit a TM entry in this TM, you see these attributes:

If you didn't want these attributes to appear, you could move them out of the Visible Attributes box.