- (education, Britain, Ireland) In the UK and Ireland, a state school attended between the ages of 11 and 16 or 18.
- 2019 October, James Abbott, “Esk Valley revival”, in Modern Railways, page 77:
- One of the key roles played by the Whitby line is the transport of children from rural spots along the branch to secondary school in the coastal town.
- (education, Canada, US) The federally designated, graduation-separated classification of grades 9–12 (approximately ages 14–18), regardless of whether they are compiled together in one school or separate from the other grades.
- (education, Hong Kong) School with education level between primary school and university.
- (education, Singapore) middle school; junior high school; a school that one attends between the ages of 12-17 (equivalent of grades 7-10 in North America, and years 7-10 in Australia)
- high school (equivalent in the US)