How to define a "variable" so I can use it in both a calculated column and a filter

Hello all

I've created a model which contains a calculated column and a filter, and saved it. Both uses a list of consultant names. However, I'd love to define this list only once and not within each of the calc column and filter. How can I do that? Is there a mechanism to define a "variable", being a list of names, so I can use that variable in both the calc column and filter?

Thanks so much.