tamp

Etymology 1

Probably a back-formation from tampin (misinterpreted as tamping), a variant of tampion.

verb

1. (blasting) To plug up with clay, earth, dry sand, sod, or other material, as a hole bored in a rock.
2. To drive in or pack down by frequent gentle strokes
   Tamp earth so as to make a smooth place.
   Typically for the 'get-on-with-it' era, the railway and military worked like demons to restore the vital rail link. The crater was rapidly filled in and the earth tamped solid, the wreckage was removed by breakdown trains, new rails and sleepers were rushed forward by willing hands, and US Army bulldozers piled in. By 2020 on the same day, both tracks were open for traffic again where there had been a gaping pit just hours before. January 12 2022, Benedict le Vay, “The heroes of Soham...”, in RAIL, number 948, page 43

Etymology 2

Perhaps confusion with damp.

verb

1. (transitive) To reduce the intensity of.
   A single thought tamped her outrage: the chance that Meredith wasn't alone in her suspicions. 2013, Kristina McMorris, The Pieces We Keep
   Whatever doubts she struggled with, they hadn't tamped her hunger for him. 2014, Christy Carlyle, Scandalous Wager
   A small bit of relief tamped her initial trepidation. 2017, Ari Thatcher, Loving Her Alphas
   Lucy bit the inside of her cheek and tamped her anger down. 2020, Jessie Gussman, An Amish Sanctuary