東西
とうざい · touzai · JLPT N2 · noun
west
東 (east) + 西 (west) = 'east and west', which together means the whole country
Read the two characters separately: 東 = east, 西 = west. Put together, the pair names the whole span of the land from one end to the other.
西 — top 覀 (cover) + bottom 儿 (legs); originally a bird in nest
Originally a pictograph of a bird settling into its nest at dusk. Because birds return to roost when the sun sets in the west, the character was borrowed to mean 'west.' The original 'nest' meaning was later written with 棲/栖.