Pieanne - I don't know the medical terminology for Tourette's - if it is a condition, an illness, or whatever. But I don't think any of your four choices work very well in English. " Although I know the two words are spelled differently, if I read "tic-illness" I tend to think of a desease spread by blood-sucking insects, like Rocky Mountain Spotted Tick Fever.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.