abnormality
mental defectiveness
room-temperature IQ
nonreceptivity
retardancy
brainpower
subnormality
intellectual disability
mental deficiency
subnormal
moronity
not the sharpest tool in the shed
not the sharpest tool in the box
mental dexterity
not the sharpest knife in the drawer
noetic
nimbleness
retardation
feeblemindedness
sophomania
mental age
unintelligence
vacancy
stupidass
retardate
dysrationalia
developmental disability
obtundation
quick-wittedness
mental quickness
quickness
failure
loss of consciousness
hyporesponsiveness
enough sense to pound sand into a rathole
deacceleration
discerptibleness
sleep
idiot savant
simple
capacity
retardedness
subfunctioning
simpleton
fluctuability
nonretraction
imbecility
noesis
induplication