Macadamia nut oil is a natural vegetable oil extracted from the nuts of the macadamia tree. It's a versatile oil that's rich in monounsaturated fats like oleic acid, as well as other beneficial compounds including vitamins and antioxidants. In skincare, macadamia nut oil is used for its hydrating and emollient properties in creams, lotions, serums and haircare products that soften and nourish hair.