理解 (rikai) means understanding or comprehension. It's the ability to grasp the meaning or significance of something, whether it's a concept, a language, or someone's feelings. It implies mental processing and insight. For example, '彼の話が理解できない。' (I can't understand what he's saying.)

理解 (りかい) は物事の意味や内容をわかること。言葉や人の気持ちを把握する時に使います。例：彼の説明を理解した。