retard vs half-wit

retard and half-wit both are nouns.

Word	Noun	Adjective	Verb	Adverb
retard	Yes	No	Yes	No
half-wit	Yes	No	No	No

As nouns, retard and half-wit are synonyms defined as:

Other synonyms of retard include changeling, cretin, idiot, imbecile, moron.

retard (noun)	half-wit (noun)
a person of subnormal intelligence	a stupid incompetent person
	a person of subnormal intelligence

retard (verb)	half-wit (verb)
lose velocity; move more slowly
cause to move more slowly or operate at a slower rate
slow the growth or development of
be delayed