add-in(A supplemental program that can extend the capabilities of an application program); add-on(A device that is traditionally added to the base computer system to increase functionality, such as audio, networking, graphics, or SCSI controller)
additive(substancje dodawane do produktu w małych ilościach, mające zmienić jego własności chemiczne lub stan fizyczny; Substances mixed in small quantities with another product to modify its chemical or physical state. Additives are used to make food look visually more attractive, in the case of colouring agents, as well as to preserve and extend the life of the product)
