noun
hard-to-get-into school; elite school; highly-selective school
Refers to a school with a highly competitive entrance examination, typically a prestigious junior high, high school, or university.
彼は難関校に合格した。
He passed the entrance exam for a highly-selective school.
難関校を目指して勉強している。
I'm studying hard aiming for a top-tier school.
名門校 emphasizes a school's long-standing prestige and tradition, whereas 難関校 focuses on the difficulty of its entrance exams.
Compound of 難関 (difficult barrier) + 校 (school).