trial court vs tribunal

trial court and tribunal both are nouns.

Word	Noun	Adjective	Verb	Adverb
trial court	Yes	No	No	No
tribunal	Yes	No	No	No

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

trial court: the first court before which the facts of a case are decided
tribunal: an assembly (including one or more judges) to conduct judicial business

Other hypernyms of trial court include court, judicature.

trial court (noun)	tribunal (noun)
the first court before which the facts of a case are decided	an assembly (including one or more judges) to conduct judicial business