Actually, 'punishment' would be a better tag than 'discipline' because discipline has two meanings; one as a synonym for punishment, the other for the kind of self-discipline which keeps you from getting into trouble in the first place.
Toawa, many words have multiple meanings. For example, "mister_ruler" could also mean a mister that ruled over others, like a king. No reason to be pointlessly technical.
Also, if you search up the definition of discipline you get:
"3. punishment inflicted by way of correction and training."
So, discipline is not simply a synonym of punishment, but a type of punishment, or punishment with purpose.