quaternity vs IV

quaternity and IV both are nouns.

Word	Noun	Adjective	Verb	Adverb
quaternity	Yes	No	No	No
IV	Yes	No	No	No

As nouns, quaternity and IV are synonyms defined as:

Other synonyms of quaternity include 4, four, foursome, Little Joe, quadruplet, quartet, quatern, quaternary, quaternion, tetrad.

quaternity (noun)	IV (noun)
the cardinal number that is the sum of three and one	administration of nutrients through a vein
	the cardinal number that is the sum of three and one