savant syndrome vs retardation

savant syndrome and retardation both are nouns.

Word	Noun	Adjective	Verb	Adverb
savant syndrome	Yes	No	No	No
retardation	Yes	No	No	No

As nouns, retardation is a hypernym of savant syndrome; that is, retardation is a word with a broader meaning than savant syndrome:

savant syndrome: A condition in which a person with a mental disability, such as an autism spectrum disorder, demonstrates profound and prodigious capacities or abilities far in excess of what would be considered normal.
retardation: lack of normal development of intellectual capacities

Other hypernyms of savant syndrome include brilliance, genius, backwardness, mental retardation, slowness, subnormality.

savant syndrome (noun)	retardation (noun)
A condition in which a person with a mental disability, such as an autism spectrum disorder, demonstrates profound and prodigious capacities or abilities far in excess of what would be considered normal.	the act of slowing down or falling behind
	a decrease in rate of change
	lack of normal development of intellectual capacities
	any agent that retards or delays or hinders
	the extent to which something is delayed or held back