# rollback
## English
### Etymology

The noun is a deverbal from roll back. The verb is a back-formation from the noun despite being redundant to roll back.

### Pronunciation

* Audio (US):(file)

### Noun

rollback (countable and uncountable, plural rollbacks)
* A return to a prior state by undoing some operation, especially of policy or price changes.
** 2001 April 8, “Environmental Rollbacks”, in The New York Times‎, →ISSN:The mining industry also had a hand in two other rollbacks. One was a decision to withdraw a Clinton rule that reduced by 80 percent the permissible standard for arsenic in drinking water.
** 2004, Paul Robert Milgrom, Putting Auction Theory to Work, page 19:A bidder that knows it may acquire power at a lower price if it withdraws demand early will be more inclined to do so than a bidder that knows it cannot cause a price rollback.
** 2019 April 10, Coral Davenport, “Automakers Plan for Their Worst Nightmare: Regulatory Chaos After Trump’s Emissions Rollback”, in The New York Times‎, →ISSN:Although Mr. Trump has billed his rollback as a boon to the auto industry, automakers say the split-market outcome would be a logistical and financial nightmare for them.
* A withdrawal of military forces.
* (databases) An operation which returns a database, or group of records in a database, to a previous state (normally to the previous commit point).
* The situation where a rollercoaster fails to reach the top of a hill and instead rolls backward.
* (informal, automotive) A form of flatbed truck adapted or designed specifically as a tow truck or for transporting other vehicles.
    Synonym: slide truck
* (political science) The strategy of forcing a change in the major policies of a state, usually by replacing its ruling regime, or by totally annihilating an enemy's armed forces and occupying the country, as was done in World War II to Italy, Germany, and Japan.
    Synonym: regime change
    Coordinate terms: containment, détente
** 2004 December 16, Seumas Milne, “The struggle is no longer against religion, but within it”, in The Guardian‎:During the 1990s the Pope, who played such a central role in the rollback of communism, was one of the few international figures who could be heard speaking out against the new capitalist order.
** 2017 May 28, Godfrey Hodgson, “Zbigniew Brzezinski obituary”, in The Guardian‎:Politically, Brzezinski was a centrist, or conservative, Democrat. He criticised both the Eisenhower administration’s “rollback” policy towards communism in Europe, and the Nixon-Kissinger detente.
* (aviation) An uncommanded reduction in the thrust of a jet engine.
** 2010 February 9, Air Accidents Investigation Branch, “1.11.3 Engine oil recorded data”, in Report on the accident to Boeing 777-236ER, G-YMMM, at London Heathrow Airport on 17 January 2008‎, archived from the original on 16 June 2022, page 44:The data was examined with respect to oil pressure. This showed that both the left and right engines' oil pressure generally follow each other until the start of the final acceleration, which resulted in first the right and then the left engines rolling back. The left engine oil pressure rose, as expected, as the engine accelerated: the right engine pressure, however, started to decrease, even though the engine was also accelerating prior to its rollback. Whilst, this observation, on the right engine, was based on only a few data points, it can be inferred that this was due to an oil temperature increase at, or close to, the start of the final acceleration. However, the loss of QAR data so close to the left engine rollback meant that it was not possible to draw a similar conclusion for the left engine.

#### Translations

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### Verb

rollback (third-person singular simple present rollbacks, present participle rollbacking, simple past and past participle rollbacked)
* (transitive, computing, databases) To return to the previous state.
    The server is unstable, we need to rollback the changes.
* (intransitive, aviation, of a jet engine) To reduce thrust without having been commanded to do so.
** 2010 February 9, Air Accidents Investigation Branch, “1.16.4.2 Full-scale engine testing (L12)”, in Report on the accident to Boeing 777-236ER, G-YMMM, at London Heathrow Airport on 17 January 2008‎, archived from the original on 12 April 2022, page 92:The first test involved placing the restriction immediately upstream of the FOHE. As it was known that the engine would almost certainly rollback during the first acceleration attempt, only the fourth accident acceleration was attempted: the rollback occurred as predicted. Testing was also conducted with the restriction at the LP pump inlet, with the rollback also occurring as predicted during the fourth acceleration.

#### Synonyms

* roll back

#### Translations
### Anagrams

* backroll, corkball