Definition of "mitigation"

Two golden hours, in which the astonishing news of the intended party was revealed to Louisa, with all of its contrivances, expenses, and mitigations, so far as they were elucidated, were given and said to be "done in her honour;"...

1838 (date written), L[etitia] E[lizabeth] L[andon], chapter XVII, in Lady Anne Granard; or, Keeping up Appearances. […], volume I, London: Henry Colburn, […], published 1842, page 213

One possible drought mitigation strategy for Afghanistan is to divert excess water from water-rich river basins to water-scarce river basins in cases where this is technologically, economically and environmentally feasible.

2004, Bhattacharya, K., Azizi, P. M., Shobair, S, S,, Mohsini, M. Y., Drought impacts and potential for their mitigation in southern and western Afghanistan, IWMI

Much of the arable land acquired by HS2 is being used for mitigation planting, in an attempt to achieve the goal set by HS2 Ltd for Phase 1, which will mean there should be no measurable loss of biodiversity after construction of the line compared with what was there before.

2023 August 23, Chris Howe, “Green screen: HS2's route through the shires”, in RAIL, number 990, page 34