母校
ぼこう · bokou · JLPT N1 · noun
alma mater
🏫 母 (mother) + 校 (school) = mother school: the school that raised you
母 is the character for mother and 校 means school, so 母校 literally says the school that gave birth to your learning. Use it for the school you once attended, the one you still feel tied to.
母 — pictograph of kneeling woman with two breast dots
母 is a pictograph derived from 女 (woman) with two added dots representing breasts, marking a nursing mother. The earliest oracle bone forms show a kneeling figure with prominent dots on the chest. The meaning has stayed remarkably stable, denoting 'mother' and by extension 'female' or 'source/origin'.