pilot program vs trial

pilot program and trial both are nouns.

Word	Noun	Adjective	Verb	Adverb
pilot program	Yes	No	No	No
trial	Yes	No	No	No

As nouns, trial is a hypernym of pilot program; that is, trial is a word with a broader meaning than pilot program:

Other hypernyms of pilot program include run, test.

pilot program (noun)	trial (noun)
activity planned as a test or trial	the act of testing something
a program exemplifying a contemplated series; intended to attract sponsors	(law) the determination of a person's innocence or guilt by due process of law
	the act of undergoing testing
	trying something to find out about it
	an annoying or frustrating or catastrophic event
	(sports) a preliminary competition to determine qualifications