tam·​per | \ ˈtam-pər How to pronounce tamper (audio) \
tampered; tampering\ ˈtam-​p(ə-​)riŋ How to pronounce tampering (audio) \; tampers

Definition of tamper

 (Entry 1 of 2)

intransitive verb

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


tamp·​er | \ ˈtam-pər How to pronounce tamper (audio) \
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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Other Words from tamper


tamperer \ ˈtam-​pər-​ər How to pronounce tamperer (audio) \ noun, plural tamperers
tamperproof \ ˈtam-​pər-​ˌprüf How to pronounce tamperproof (audio) \ adjective

Examples of tamper in a Sentence

Recent Examples on the Web: Verb The same day, a jury found Trump’s longtime adviser Roger Stone guilty of lying to Congress and witness tampering over the Russian interference that helped elect Trump in 2016. BostonGlobe.com, "But his shortcomings, like those of his Democratic rivals, are minuscule compared to the appalling qualities Trump displays daily. Democrats are playing not just by different rules, but an entirely different game.," 17 Nov. 2019 Why it could be prosecuted as witness tampering Federal criminal law contains a broad prohibition against illegitimately affecting the presentation of evidence in hearings. Danny Cevallos, NBC News, "Trump tweeted as Marie Yovanovitch testified: Was it witness tampering?," 16 Nov. 2019 Allegations about him tampering with customers' drinks first arose in 2014, in a search warrant affidavit. Bruce Vielmetti, Milwaukee Journal Sentinel, "Operator of former Cedarburg fondue restaurant may have drugged more than 20 young women, prosecutor says," 14 Nov. 2019 Stone, a longtime Trump friend and ally, is charged with witness tampering and lying to Congress about his attempts to contact WikiLeaks about the damaging material during the 2016 presidential campaign. Michael Balsamo, chicagotribune.com, "Roger Stone trial testimony ends with talk he tried to contact Jared Kushner to ‘debrief’ him about hacked emails," 12 Nov. 2019 Johnson, his brother and his former girlfriend are accused of conspiracy to commit witness tampering for allegedly trying to get the sisters to change their testimony. David Owens, courant.com, "Hartford man sentenced to 50 years in prison for gunpoint rape of two homeless sisters on Thanksgiving Day 2017," 12 Nov. 2019 Stone, a Fort Lauderdale resident and longtime Trump ally, is charged with witness tampering and lying to Congress about his attempts to contact WikiLeaks about the damaging material during the 2016 presidential campaign. Michael Balsamo, sun-sentinel.com, "Stone wanted to ‘debrief’ Kushner on DNC email hack," 12 Nov. 2019 Michael Warren, 33, was arrested and charged with leaving the scene of a traffic crash involving death and tampering evidence. Levi Edwards | Ledwards@al.com, al, "3 arrested in Panama City Beach hit-and-run death of Alabama woman," 12 Nov. 2019 To report possible tampering to the KDA, call 502-573-0282 or email ag.web@ky.gov. Billy Kobin, The Courier-Journal, "'Goblins at the gas pump': Kentucky officials urge drivers to beware credit card skimmers," 30 Oct. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tamper.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of tamper


1567, in the meaning defined at sense 2


circa 1864, in the meaning defined above

History and Etymology for tamper


probably from Middle French temprer to temper, mix, meddle — more at temper entry 2

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Statistics for tamper

Last Updated

20 Nov 2019

Time Traveler for tamper

The first known use of tamper was in 1567

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More Definitions for tamper


tam·​per | \ ˈtam-pər How to pronounce tamper (audio) \
tampered; tampering

Kids Definition of tamper

: to interfere or change in a secret or incorrect way Someone was tampering with the official records.

Legal Definition of tamper

1 : to bring improper influence to bear (as by bribery or intimidation) used with with tampered with the jurors
2 : to alter or interfere in an unauthorized or improper manner used with with tampered with evidence

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More from Merriam-Webster on tamper

Spanish Central: Translation of tamper

Nglish: Translation of tamper for Spanish Speakers

Britannica.com: Encyclopedia article about tamper

Comments on tamper

What made you want to look up tamper? Please tell us where you read or heard it (including the quote, if possible).


to speed up the process or progress of

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