junior vs seniority

junior and seniority both are nouns.

Word	Noun	Adjective	Verb	Adverb
junior	Yes	Yes	No	No
seniority	Yes	No	No	No

junior (noun)	seniority (noun)
the younger of two persons	the property of being long-lived
a third-year undergraduate	higher rank than that of others especially by reason of longer service
term of address for a disrespectful and annoying male

junior (adjective)	seniority (adjective)
younger; lower in rank; shorter in length of tenure or service
used of the third or next to final year in United States high school or college
including or intended for youthful persons