petit jury vs jury

petit jury and jury both are nouns.

Word	Noun	Adjective	Verb	Adverb
petit jury	Yes	No	No	No
jury	Yes	No	No	No

As nouns, jury is a hypernym of petit jury; that is, jury is a word with a broader meaning than petit jury:

petit jury: a jury of 12 to determine the facts and decide the issue in civil or criminal proceedings
jury: a body of citizens sworn to give a true verdict according to the evidence presented in a court of law

petit jury (noun)	jury (noun)
a jury of 12 to determine the facts and decide the issue in civil or criminal proceedings	a body of citizens sworn to give a true verdict according to the evidence presented in a court of law
	a committee appointed to judge a competition