rollback

noun

1. (countable, uncountable)A return to a prior state by undoing some operation, especially of policy or price changes.

   “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.”

   “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.”

   “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.”

2. (countable, uncountable)A return to a prior state by undoing some operation, especially of policy or price changes.
3. (countable, uncountable)A return to a prior state by undoing some operation, especially of policy or price changes.

   “Near-synonyms: reversion, revert (sometimes synonymous)”

4. (countable, uncountable)The situation where a rollercoaster fails to reach the top of a hill and instead rolls backward.
5. (countable, informal, uncountable)A form of flatbed truck adapted or designed specifically to carry other vehicles, for use in recovery (wrecking, salvage) or for transporting.

   “Near-synonym: tow truck (loosely often synonymous)”

6. (countable, uncountable)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.

   “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.”

   “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.”

7. (countable, uncountable)An uncommanded reduction in the thrust of a jet engine.

verb

1. (transitive)To return to the previous state.

   “The server is unstable, we need to rollback the changes.”

2. (intransitive)To reduce thrust without having been commanded to do so.

   “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.”