Explanandum
（重定向自Explanans）
An explanandum (a Latin term) is a phenomenon that is to be explained and its explanans is the explanation of that phenomenon. For example, one person may pose an explanandum by asking "Why is there smoke?", and another may provide an explanans by responding "Because there is a fire". In this example, "smoke" is the explanandum, and "fire" is the explanans.