Create a CASE statement calculation.
CASE professional title
WHEN "END" THEN "Endocrinologist"
WHEN "abbreviation here" THEN "the full name"
Then add the calculated field to the tooltip or detail mark and Add it to the tool tip as Professional Title: <Professional Title>
OR if it's a particularly long list, then create a validation table in a separate sheet and inner joining the the two based on the titles and then adding the titles to tooltip or detail.
Hope this helps!
Im an idiot. I could just duplicate the field and change the alias.
Well, you're not an idiot, but YES-- that's a good way to go to preserve both the long & short versions