mitigate

To make less severe or intense; moderate or alleviate. synonym: relieve.

To make alterations to (land) to make it less polluted or more hospitable to wildlife.

To take measures to moderate or alleviate (something).

To be a strong factor against (someone or something); hinder or prevent.

To make milder or more tolerable; reduce in amount or degree, as something objectionable, reprehensible, distressing, harmful, etc.; moderate; alleviate; assuage.