cobalamin vs vitamin B12

cobalamin and vitamin B12 both are nouns.

Word	Noun	Adjective	Verb	Adverb
cobalamin	Yes	No	No	No
vitamin B12	Yes	No	No	No

As nouns, cobalamin and vitamin B12 are synonyms defined as:

cobalamin and vitamin B12: a B vitamin that is used to treat pernicious anemia

Other synonyms of cobalamin include antipernicious anemia factor, cyanocobalamin.

cobalamin (noun)	vitamin B12 (noun)
a B vitamin that is used to treat pernicious anemia	a B vitamin that is used to treat pernicious anemia