SynonymDefinitionAntonym.com - English Synonym Dictionary

The act of adding a component or accessory to something that did not have it when it was manufactured

A component or accessory added to something after it has been manufactured

Substitute new or modernized parts or equipment for older ones

Fit in or on an existing structure, such as an older house

Provide with parts, devices, or equipment not available or in use at the time of the original manufacture