low-birth-weight baby vs low-birth-weight infant

low-birth-weight baby and low-birth-weight infant both are nouns.

Word	Noun	Adjective	Verb	Adverb
low-birth-weight baby	Yes	No	No	No
low-birth-weight infant	Yes	No	No	No

As nouns, low-birth-weight baby and low-birth-weight infant are synonyms defined as:

low-birth-weight baby and low-birth-weight infant: an infant born weighing less than 5.5 pounds (2500 grams) regardless of gestational age

low-birth-weight baby (noun)	low-birth-weight infant (noun)
an infant born weighing less than 5.5 pounds (2500 grams) regardless of gestational age	an infant born weighing less than 5.5 pounds (2500 grams) regardless of gestational age