What happens when you stop doing smart stuff and your intelligence slowely drips out of your ears and onto the floor.

Dumber means even more stupid

completely devoid of any shred of anything that even remotely resembles inteligence

Dumber is the word used by people who are trying to be funny by making what sounds like a grammatically incorrect sentence while it actually is perfectly correct.

To dumb down, to make dumber

dumberer dumerer (adj)- very far below anything even remotly resembling intelligence at all

1. "More dumb than"
2. Having a lower intelligence than a certain person/thing.