higher technical school
Historical term for a type of pre-WWII Japanese technical college, roughly equivalent to a present-day technical college or institute of technology.
His grandfather graduated from a higher technical school before the war.
Modern successor institution (technical college), often abbreviated as 高専 (こうせん).
Broader category of pre-war specialized schools, which included higher technical schools.
Compound of 高等 (higher), 工業 (industry/engineering), and 学校 (school). The term reflects the pre-war Japanese educational system.