make nonsense of something

make (a) nonsense of (something)

To lessen something serious or important to a silly or ridiculous level. The candidate has been making a nonsense of the whole political process, but many voters feel that that is just what's needed. I don't appreciate you making nonsense of this class with your rude remarks and obnoxious behavior.
See also: make, nonsense, of

make (a) ˈnonsense of something

reduce the value of something by a lot; make something seem ridiculous: If people can bribe police officers, it makes a complete nonsense of the legal system.
See also: make, nonsense, of, something