half-wit vs changeling

half-wit and changeling both are nouns.

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

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

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

half-wit (noun)	changeling (noun)
a stupid incompetent person	a child secretly exchanged for another in infancy
a person of subnormal intelligence	a person of subnormal intelligence