A tribunal is a body with official power to hear one particular kind of case and decide it — employment disputes, immigration appeals, war crimes, medical misconduct. It is court-like: it hears evidence, both sides speak, and its decision binds people. But it is usually narrower and less formal than a full court — often the people deciding are not all judges, some are experts in the field, and the rules about evidence and dress and procedure are lighter. This word is much more common in British English and in international law than in American English; in Britain, an ordinary worker who is unfairly dismissed goes to an employment tribunal, and that is an everyday phrase there. Internationally you meet it in names like the International Criminal Tribunal for the former Yugoslavia. There is also an older, grander use meaning the seat or bench where a judge sits, and by extension any place of judgement — 'the tribunal of history', 'the tribunal of public opinion' — which is literary rather than legal. Americans more often say 'board', 'panel', or 'commission' for the everyday sense.