Writers employ "periphery" to evoke both concrete and abstract boundaries. In mathematical and technical contexts, the term precisely defines the edges or contours of shapes and mechanisms—for instance, describing the limit between a circle and its tangent [1] or the teeth on a cog-wheel [2]. Meanwhile, in more metaphorical or observational writings, "periphery" denotes the outer reaches of systems, whether in nature or human experience, as when it outlines the margins of a forest [3] or signifies the farthest limits of one’s affections [4]. Such uses reveal how the word can oscillate between denoting physical borders and symbolizing conceptual margins across diverse literary settings.