The word 回收 is formed by combining two meaningful characters: 回, which carries the core idea of "returning" or "coming back", and 收, which means "to collect" or "to gather". Their conceptual union creates a single, unified notion where the action of collecting (收) is specifically directed at items in order to bring them back (回) into a system or process, thus naturally conveying the meaning "to recycle", "to reclaim", or "to recover".