"Medical" here means "matching what the average person would think of when told it is medical". That is, the word is intended to communicate, and what it communicates is misleading to a large portion of the intended audience.
Tabooing Your Words has the purpose of removing a disagreement about word definitions from these discussions. The substitution you made does not help, since now the discussion could continue in the direction of arguing about what the average person thinks of the word (which is pretty close to the definition of definition). (This feels close to Fighting the Hypothetical.)
(Am I intuiting this right that you're not sure you could find a proper substitution that the others could not prove bad at capturing what you wanted to say by using it to prove your point ...
Over at Scott Adams' Blog you can find a very fine example of using the 'Rationality Engine' to solve the social problem of assisted dying.