Definition of tamper
(Entry 1 of 2)
1a : to interfere so as to weaken or change for the worse
—used with withdid not want to tamper with tradition
b : to try foolish or dangerous experiments
—used with with
c : to render something harmful or dangerous by altering its structure or composition
was charged with tampering with consumer products
2a : to carry on underhand or improper negotiations (as by bribery)
b : to inflict physical harm, threats, intimidation, or corrupt persuasion with the goal of influencing or preventing a witness's testimony : to engage in witness tampering —used with withThese alleged efforts were the basis for Mueller's accusation that Manafort was tampering with a witness, attempting to coach testimony, which would have violated the terms of his bail.— Franklin Foer
tamper
noun plural tampers
Definition of tamper (Entry 2 of 2)
: a tool for tamping : tamp entry 2 Using a tamper, tamp the coffee down into the filter …— Lexa Roséan After each truckload of earth fell onto the cobblestones of the Piazza's perimeter, a steamroller flattened it, and five relaxed-looking workmen … patted it smooth with shovels and wooden tampers, and hosed it down.— Lis Harris
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Time Traveler for tamper
The first known use of tamper was in 1567
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