The word 栅栏 is formed through the complementary combination of two characters that each contribute a specific aspect of the same core idea. 栅 (zhà) originally depicts a barrier made of upright wooden stakes or poles, emphasizing the vertical, picket-like elements. 栏 (lán) refers to a railing, fence, or enclosure, often implying horizontal crosspieces or a more general barrier function. When paired, they merge their specific images, the vertical stakes from 栅 and the enclosing rail concept from 栏, to create a single, more complete and vivid mental picture of a constructed fence or railing.