The word 归还 (guīhuán) is a compound formed by combining two characters with synonymous meanings, both centered on the concept of "returning". The first character, 归 (guī), means to go back, revert, or return to an original state or place. The second character, 还 (huán), specifically means to give back, return, or repay something. When paired together, they create a reinforced and formal term that explicitly means to return something (often a borrowed or taken item) to its original owner or rightful place, emphasizing the complete act of restitution. This structure of combining near-synonyms is a common method in Chinese for forming precise and often more literary or formal vocabulary.