The word 'west' originates from the Old English 'west', which itself derives from the Proto-Germanic 'westrą'. This term is fundamentally linked to the setting sun, as it is cognate with the Latin 'vesper' (evening, west) and the Greek 'hesperos' (evening star, west). The core concept across these languages is the direction of the sunset, a crucial spatial marker tied to the daily solar cycle. From this concrete, astronomical reference, the meaning expanded to denote a cardinal direction and, by extension, any region lying in that direction from a given point.

The word 'west' is a simplex word of Germanic origin. It functions as a complete, unanalyzable root in modern English.