遗传 (yíchuán) literally combines 遗 (yí, 'to leave behind; legacy') and 传 (chuán, 'to transmit; pass on'), together meaning the biological transmission of traits from parents to offspring through genes. As a noun, it refers to 'heredity' or 'genetic inheritance'; as a verb, it means 'to inherit genetically' or 'to be passed down genetically.' It is commonly used in discussions about physical features (e.g., eye color), health conditions (e.g., diabetes), or behavioral tendencies that run in families.

This term appears frequently in medical, scientific, and everyday contexts — for example, when explaining why a child resembles a parent or why certain diseases affect multiple generations. Unlike general inheritance (继承 jìchénɡ), which can refer to property or culture, 遗传 specifically concerns biological, DNA-based transmission and cannot be used for non-biological legacies.