a component or accessory added to something after it has been manufactured
"The mechanic suggested we retrofit new LED headlights into our older car model."
the act of adding a component or accessory to something that did not have it when it was manufactured
"the court ordered a retrofit on all automobiles"
Something that has been retrofitted
"The old factory building was finally retrofitted with modern solar panels to meet new energy standards."
provide with parts, devices, or equipment not available or in use at the time of the original manufacture
"They car companies retrofitted all the old models with new carburetors"
fit in or on an existing structure, such as an older house
"The mansion was retrofitted with modern plumbing"
substitute new or modernized parts or equipment for older ones
"The laboratory retrofitted to meet the safety codes"
To add or substitute new parts or components to some device, structure etc., that were not previously available; to modernize
"The city plans to retrofit every old apartment building with energy-efficient windows and solar panels."
of, relating to, or being a retrofit
"The building's energy efficiency upgrades were part of a major retrofit that brought the old factory up to modern standards."