Every language has its own key words, which reflect the core values of the culture. Consequently, cultures can be revealingly studied, compared, and explained to outsiders through their key words. But to be able to study, compare, and explain cultures in terms of their key words, we need a culture-independent analytical framework. A framework of this kind is provided by the natural semantic metalanguage developed by the author and colleagues over the last two decades. In the present article, the author explores and analyzes six Japanese concepts widely regarded as being almost more that any others culture-specific and culturally revealing – amae, enryo, wa, on, giri, and seishin – and shows how the use of the natural semantic metalanguage (based on universal semantic primitives) helps to make these concepts clear and how it facilitates better insight into Japanese culture and society (Japanese language, Japanese culture, cross-cultural semantics, key words, core values)