A response you can give when someone says something so idiotic it fries your braincells.

dumb-head
Definitions include: an unintelligent person.
Homer
Definitions include: a simple minded person, never cognizant of the world around them; MORON.
dumb bunny
Definitions include: an unintelligent person.
numptie
Definitions include: A fool or idiot.
pud-whack
Definitions include: a stupid person.
mule head
Definitions include: MORAN, someone stupid .
dildo
Definitions include: a vaguely (or precisely) penis-shaped object used for sexual stimulation.
muppet
Definitions include: an idiotic or incompetent person.
lunkhead
Definitions include: a very unintelligent person.
dumbf*ck
Definitions include: an unintelligent person.
jughead
Definitions include: a fool.
snapperhead
Definitions include: an idiot.
Quayle
Definitions include: stupid or dumb.
stoopid
Definitions include: spelling of stupid.
cherries
Definitions include: stupid. (also used as grapes).

When someone is being a fucking idiot

The act to where you're acting so stupid that you start doin dumb shit.

When someone is acting dumb and is stupid

fuck you dumb ass bitch