演变 (yǎn biàn) means 'evolution' — the gradual, often natural process of change and development over time. The first character 演 (yǎn) originally means 'to perform' or 'to unfold', suggesting a progressive, unfolding process; the second character 变 (biàn) means 'to change' or 'to transform'. Together, they emphasize not just any change, but a sustained, directional, and usually organic transformation — especially in biological, linguistic, cultural, or historical contexts.

This word is commonly used in formal or academic writing and speech, such as discussing how species adapt, how languages shift across centuries, or how social customs develop. It implies continuity and causality: earlier forms lead logically to later ones. Unlike the more general 变化 (biàn huà, 'change'), 演变 suggests deeper structural or systemic development, often over long periods — think of Darwinian evolution or the evolution of Chinese characters from oracle bone script to modern forms.