A light insult you would call one of your friends or siblings/cousins were they to slip up while doing something simple like spreading butter on toast.
An intelligence insult ....when you go to stick your head out the car window... or any window to spit or scream and you forget to roll the window down....thoughtless...careless not paying attention DINK ; THE sound a window makes when head is tapped on glass..... verb...adj... pronoun