The word "榛仁" is formed by combining the character "榛", which refers to the hazel tree or hazelnut, with "仁", which means the kernel or seed of a nut. Together, they create a compound term where "榛" specifies the source and "仁" denotes the edible inner part, resulting in the meaning "hazelnut kernel". This formation directly derives from the literal semantic contributions of each character to indicate a specific natural product.