letters of administration vs jurisprudence

letters of administration and jurisprudence both are nouns.

Word	Noun	Adjective	Verb	Adverb
letters of administration	Yes	No	No	No
jurisprudence	Yes	No	No	No

letters of administration (noun)	jurisprudence (noun)
legal document naming someone to administer an estate when no executor has been named	the branch of philosophy concerned with the law and the principles that lead courts to make the decisions they do
	the collection of rules imposed by authority