Custom-making refers to the act of creating something unique and tailored to specific requirements. The antonym of custom-making would be mass production or standardization. Mass production is the manufacturing of goods in large quantities using standardized designs and materials with little consideration for individual needs or preferences. Standardization, on the other hand, implies conforming to a set of prescribed standards or norms rather than customizing a product. The antithesis of custom-making is the practice of providing generic or off-the-shelf products that do not consider the customer's unique needs, tastes, or preferences. In this sense, custom-making represents an innovative and personalized approach to product creation, while standardization and mass production represent more conventional methods.