还原 (huán yuán) literally means 'return to original' — the character 还 (huán) means 'to return' or 'to give back', and 原 (yuán) means 'original', 'source', or 'pristine state'. Together, they form a verb meaning 'to restore something to its original condition' — whether that’s a physical object, a chemical substance, a digital file, or even a person’s health. It implies reversing change, undoing damage, or bringing back authenticity.

This word is commonly used in scientific, medical, and technical contexts — for example, restoring corrupted data, reversing oxidation in chemistry (e.g., reducing metal oxides), or rehabilitating bodily functions after illness. It can also appear metaphorically, such as restoring trust or reviving traditional practices. Unlike the more general 恢复 (huīfù), 还原 emphasizes fidelity to the *exact* prior state, often implying precision or technical intervention.