1.
national polity; national structure; form of government
The fundamental character or political structure of a nation. Historically significant in prewar Japan as an ideological concept centering on the emperor system.
2.
National Sports Festival
Short for 国民体育大会 (National Sports Festival), an annual multi-sport competition held in a different prefecture each year. Renamed to 国民スポーツ大会 in 2024, but the abbreviation 国体 remains in common use.
This word has two very different meanings depending on context. Sense 1 (国体 = national polity) is a historically loaded term, central to prewar Japanese ideology emphasizing the emperor as the foundation of the state. It appears frequently in discussions of Japanese wartime history. Sense 2 is an abbreviation of 国民体育大会, Japan's annual national athletic competition held since 1946. Context usually makes the intended meaning clear: political/historical contexts point to sense 1, sports contexts to sense 2.