jurisprudence vs relation back

jurisprudence and relation back both are nouns.

Word	Noun	Adjective	Verb	Adverb
jurisprudence	Yes	No	No	No
relation back	Yes	No	No	No

jurisprudence (noun)	relation back (noun)
the branch of philosophy concerned with the law and the principles that lead courts to make the decisions they do	(law) the principle that an act done at a later time is deemed by law to have occurred at an earlier time
the collection of rules imposed by authority