prolong, extend

廴 is formed by further elongating 彳(step with the left foot) downward. 彳 is a pictograph of a road or path, so 廴 conveys the idea of an extended road and means to lengthen or to expand. However, this meaning has been taken over by the character 延. Nowadays, 廴 is no longer used independently and only appears as a component in other characters.