changeling vs retard

changeling and retard both are nouns.

Word	Noun	Adjective	Verb	Adverb
changeling	Yes	No	No	No
retard	Yes	No	Yes	No

As nouns, changeling and retard are synonyms defined as:

Other synonyms of changeling include cretin, half-wit, idiot, imbecile, moron.

changeling (noun)	retard (noun)
a child secretly exchanged for another in infancy	a person of subnormal intelligence
a person of subnormal intelligence

changeling (verb)	retard (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