Updated keyword library

I share my keyword library between my iMac and MacBook. I notice that the library is common to each machine even if I use sessions vs my catalog.  Words used in a session are carried with the session catalog.  If I update my main library on one, then export it to import it on the other, can I delete the older versions? If I try, I get a message: "Are you sure you want to delete 'Capture One iMac...'? The library will be moved to the system recycle bin, and removed from recipes that reference it. This operation cannot be undone." I am not sure what is meant by recipes, and I do not want to loose references in the actual files.