(Offensive slang) used as a disparaging and abusive term for a
person who has intellectual disabilities, originally US.
By extension, you can use this word to describe a person who is extremely foolish,
dumb or
stupid.
Retard usage
Note: this word is pronounced as ‘
REE-
tard’, not ‘ri-
TARD’ (inoffensive sense for delay or slow down).
Note: this word is outdated and considered offensive and the senses above should be avoided.