こうとうがっこう高等学校koutougakkou
1.
An educational institution that provides advanced general and specialized education, typically attended after completing junior high school, and usually lasting three years, which may include full-time, part-time, or correspondence courses.
2.
A historical type of school that offered upper-level education to male students who completed four years of junior high school or had equivalent academic skills, and served as a preparatory school for higher education prior to the educational reforms in 1947.
Example:
彼は高等学校の生徒ではありません。