atomic number 91 vs Pa

atomic number 91 and Pa both are nouns.

Word	Noun	Adjective	Verb	Adverb
atomic number 91	Yes	No	No	No
Pa	Yes	No	No	No

As nouns, atomic number 91 and Pa are synonyms defined as:

atomic number 91 and Pa: a short-lived radioactive metallic element formed from uranium and disintegrating into actinium and then into lead

Other synonyms of atomic number 91 include protactinium, protoactinium.

atomic number 91 (noun)	Pa (noun)
a short-lived radioactive metallic element formed from uranium and disintegrating into actinium and then into lead	a unit of pressure equal to one newton per square meter
	a short-lived radioactive metallic element formed from uranium and disintegrating into actinium and then into lead