The compound "weather-worn" is a transparent combination of two deeply rooted English words. "Weather" originates from the Proto-Germanic wedrą, meaning "wind, weather," which itself may derive from the Proto-Indo-European root we-dhro-, meaning "weather, storm." "Worn" comes from the Old English verb werian, meaning to carry or use, tracing back to the PIE root wes-, "to clothe." The compound's logic is straightforwardly literal: it describes an object that has been "worn" or eroded by the persistent action of the "weather"—rain, wind, sun, and frost. This term vividly encapsulates the slow, natural process of deterioration caused by atmospheric forces, moving from the concrete actions of wearing and exposure to the abstract state of being aged and damaged by the elements.

Structure: weather (condition of the atmosphere) + worn (damaged by use) - weather: From Old English weder, meaning "air, sky, breeze, storm, weather." Its functional role is as a noun root specifying the agent of the wearing. - worn: Past participle of the verb wear, from Old English werian, meaning "to clothe, put on, carry, use up, damage by use." Its functional role is as an adjective-forming element indicating the state of being damaged.