changeling
imbecile
idiot
half-wit
retard
cretin
moron
brain
dimwit
subnormal
not the sharpest knife in the drawer
not the sharpest tool in the shed
not the sharpest tool in the box
stupidass
fuckwad
halfwit
dirtbrain
birdbrain
drool bucket
profundity
hammerhead
knucklehead
sophomania
fuckhead
dunce
pseudointellectual
blockhead
bonehead
numskull
muttonhead
dumbass
lunkhead
dunderhead
loggerhead
shithead
dotard
simpleton
fool
simple
mentally challenged
submoron
genia
stun
snitchee
divvie
unintelligent
stupid
intelligenced
lackluster
nonintellectual
half-brained
closed book
rube
midwit
four oh four
native wit
magician
intelligencelike
subintellectual
sphinx
intelligentially
cacophrenic
shallow
personage
passive source
noetic
ass sucker
submoronic
intellection
simple-mindedly
gormless
dense
idiot savant
underbrained
hayseed
chawbacon
cerebrally challenged
keenness
sharpness
thembo
battle of the brains
prehensile
room-temperature IQ
acuity
yahoo
yokel
dropkick
intellectually challenged
bumpkin
half-witted
acuteness
hick
dipshidiot
nondescript
brain cell
sap