向上
こうじょう · koujou · JLPT N1 · noun
improvement
向 — roof 宀 + mouth 口
Originally a pictograph of a house with a north-facing window, showing an opening in a wall under a roof. The early meaning was 'north window,' which extended to 'the direction something faces,' then broadly to 'toward' or 'direction.' The modern shape simplified the window into 口.
上 — horizontal line above a baseline
上 is an indicative character (指事): a short stroke placed above a longer reference line shows the concept of 'above' or 'up'. The earliest oracle-bone forms used two horizontal lines for this; the modern shape added a vertical stroke for clarity. The core meaning of 'upper, above, to ascend' has stayed stable for millennia.