retrofit

American  

[re-troh-fit, re-troh-fit, re-troh-fit] / ˈrɛ troʊˌfɪt, ˌrɛ troʊˈfɪt, ˈrɛ troʊˌfɪt /

verb (used with object)

• retrofits,
  present (3rd person singular)
• retrofitted,
  past participle,  past
• retrofit,
  past participle,  past
• retrofitting
  present participle

1. to modify equipment (in airplanes, automobiles, a factory, etc.) that is already in service using parts developed or made available after the time of original manufacture.

2. to install, fit, or adapt (a device or system) for use with something older.

   to retrofit solar heating to a poorly insulated house.

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verb (used without object)

• retrofits,
  present (3rd person singular)
• retrofitted,
  past participle,  past
• retrofit,
  past participle,  past
• retrofitting
  present participle

1. (of new or modified parts, equipment, etc.) to fit into or onto existing equipment.

2. to replace existing parts, equipment, etc., with updated parts or systems.

noun

• retrofits
  plural

1. something that has been retrofitted.

2. an instance of updating, enlarging, etc., with new or modified equipment.

   A retrofit could save thousands of dollars.

adjective

1. being or characterized by a retrofit.

   retrofit units.

retrofit British  

/ ˈrɛtrəʊˌfɪt /

verb

1. (tr) to equip (a vehicle, piece of equipment, etc) with new parts, safety devices, etc, after manufacture

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Other Word Forms

Derived Forms

• retrofittable
  adjective

Inflected Forms

Nouns

• retrofits
  plural

Participles

• retrofitting
  present
• retrofit
  past
• retrofitted
  past

Conjugated Forms

Present

• retrofit
  simple
• retrofits
  simple
• have retrofit
  perfect
• have retrofitted
  perfect
• has retrofit
  perfect
• has retrofitted
  perfect
• am retrofitting
  progressive
• are retrofitting
  progressive
• is retrofitting
  progressive
• have been retrofitting
  perfect progressive
• has been retrofitting
  perfect progressive

Past

• retrofit
  simple
• retrofitted
  simple
• had retrofit
  perfect
• had retrofitted
  perfect
• was retrofitting
  progressive
• were retrofitting
  progressive
• had been retrofitting
  perfect progressive

Future

• will retrofit
  simple
• will have retrofit
  perfect
• will have retrofitted
  perfect
• will be retrofitting
  progressive
• will have been retrofitting
  perfect progressive

Etymology

Origin of retrofit

retro- + fit ¹

Explanation

When you retrofit something, you replace old parts with new ones. You might retrofit an antique car with updated brakes and seat belts, for example. You can use retrofit as a verb, or it can be a noun meaning the new part itself, or something that's added on later. The solar panels on your two hundred year old house are a retrofit, and so is the fancy new stereo in your beat up old car. Retrofit has been around since the mid-1950s, when retroactive and refit were combined into a new word.

Example Sentences

See Examples For:

retrofit retrofits retrofitted retrofitting

The most disruptive part of the retrofit work was carried out first, and included the insulation of shared walls, flooring and the roof.

From BBC ● Aug. 21, 2026

The same is true for giving employees workplace options: Perhaps three configurations for the retrofit, each with a clear rationale, gets employees input without turning it into a second job.

From The Wall Street Journal ● Jun. 14, 2026

To use as bargaining chips for either a big name like the Milwaukee Bucks’ Giannis Antetokounmpo or, better yet, to acquire important foundational pieces to retrofit the roster around Luka Doncic?

From Los Angeles Times ● May 27, 2026

The alternative to this is to build new bespoke plants or retrofit existing facilities with new kit, from companies like Colorado-based AMP.

From BBC ● May 4, 2026

The Center has since benefitted by a forty-million-dollar retrofit, but there's still enough forest and swamp on the facility for the Border Patrol to put in tracking practice.

From The Hacker Crackdown, law and disorder on the electronic frontier by Bruce Sterling

American Airlines expects screens to be installed across its full fleet by early in the next decade, with retrofits starting in 2028.

From The Wall Street Journal ● Aug. 18, 2026

On Net Zero he proposes a "Northern Way", which subsidises the transition, retrofits, cutting bills, and building exportable locally owned industry.

From BBC ● Jul. 17, 2026

The ADS-B In retrofits might not be compatible with hundreds of planes in the U.S. commercial fleet, according to Bedford, the FAA administrator.

From The Wall Street Journal ● May 31, 2026

More recently built structures need fewer upgrades and may not require seismic retrofits to meet safety codes.

From Los Angeles Times ● Feb. 11, 2026

In South Pasadena, with a population of 26,000, building officials said earlier this year the city has no plans to create an inventory of soft-story apartment buildings or consider mandatory retrofits.

From Los Angeles Times ● Dec. 16, 2024

For excursions on land, Green Safaris’s lodges have retrofitted Land Rovers to run on batteries.

From The Wall Street Journal ● Aug. 16, 2026

Waymo’s taxis are retrofitted existing vehicles with autonomous technology added including cameras and sensors.

From Los Angeles Times ● Aug. 10, 2026

Dahlia and Mark discuss what happens when popular constitutionalism is retrofitted as originalism, and why no constitutional win, no matter how popular, is ever truly permanent.

From Slate ● Aug. 1, 2026

A vehicle was retrofitted so that Lillard could drive.

From BBC ● Jul. 14, 2026

Bratton retrofitted a city bus and turned it into a rolling station house, with its own fax machines, phones, holding pen, and fingerprinting facilities.

From "The Tipping Point" by Malcolm Gladwell

But the Passivhaus Trust - for which Baeli is a non-executive director - acknowledges retrofitting your home to this standard is "expensive".

From BBC ● Aug. 21, 2026

Across the country, entrepreneurs like Gutstadt are capitalizing on the interest by retrofitting unconventional spaces, from parking lots to distribution warehouses, with padel courts.

From The Wall Street Journal ● Jul. 22, 2026

Jones noted that the state offers grants through the Earthquake Brace+Bolt program to partially cover the cost of retrofitting older single-family homes that can slide off their foundation in an earthquake.

From Los Angeles Times ● Jun. 25, 2026

At those levels, buyers can commission their own dream homes instead of retrofitting someone else’s fantasy.

From MarketWatch ● Jun. 3, 2026

In April the government approved a legal framework to allow people to convert their petrol and diesel vehicles into electric ones, known as "retrofitting".

From Barron's ● May 3, 2026