sudden infant death syndrome vs SIDS

sudden infant death syndrome and SIDS both are nouns.

Word	Noun	Adjective	Verb	Adverb
sudden infant death syndrome	Yes	No	No	No
SIDS	Yes	No	No	No

As nouns, sudden infant death syndrome and SIDS are synonyms defined as:

sudden infant death syndrome and SIDS: sudden and unexpected death of an apparently healthy infant during sleep

Other synonyms of sudden infant death syndrome include cot death, crib death, infant death.

sudden infant death syndrome (noun)	SIDS (noun)
sudden and unexpected death of an apparently healthy infant during sleep	sudden and unexpected death of an apparently healthy infant during sleep