tam·​per | \ ˈtam-pər How to pronounce tamper (audio) \
tampered; tampering\ ˈtam-​p(ə-​)riŋ How to pronounce tamper (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 tamper (audio) \ noun, plural tamperers
tamperproof \ ˈtam-​pər-​ˌprüf How to pronounce tamper (audio) \ adjective

Examples of tamper in a Sentence

Recent Examples on the Web: Verb Experts believe that the technique could be used for further studies on mummies, giving further clues as to the object buried alongside the ancient corpses, without the need to disturb and tamper with bodies. Amy Woodyatt, CNN, "New X-ray technique reveals clues about ancient 1,900-year-old mummy," 24 Nov. 2020 In September, four of the six individuals allegedly involved in the plot admitted to their involvement and soon pleaded guilty to conspiracy to commit cyberstalking and conspiracy to tamper with witnesses. Fortune Editors, Fortune, "The biggest business scandals of 2020," 27 Dec. 2020 His girlfriend, Cecily Aguilar, faces a charge of conspiracy to tamper with evidence. New York Times, "14 Army Officials Disciplined in Fort Hood Investigation," 8 Dec. 2020 Russian state nationals accused of wielding life-threatening malware specifically designed to tamper with critical safety mechanisms at a petrochemical plant are now under sanction by the US Treasury Department. Dan Goodin, Ars Technica, "Hackers behind life-threatening attack on chemical-maker are sanctioned," 23 Oct. 2020 Government officials use Facebook to mislead their own citizens, and to tamper with elections. Adrienne Lafrance, The Atlantic, "Facebook Is a Doomsday Machine," 15 Dec. 2020 The malware goes on to tamper with certain DLL files. Dan Goodin, Ars Technica, "4 major browsers are getting hit in widespread malware attacks," 10 Dec. 2020 The video seems to imply that this opens the door for someone to tamper with election materials. Clara Hendrickson, Detroit Free Press, "Video falsely claims Detroit poll workers were trained to steal election. Here are the facts.," 11 Nov. 2020 Threats to digital security come in many shapes and sizes, but Miceli notes that criminals can tamper with the library’s digitized files or conduct a ransomware attack, in which hackers effectively hold files ransom in exchange for a hefty sum. Nora Mcgreevy, Smithsonian Magazine, "Vatican Library Enlists Artificial Intelligence to Protect Its Digitized Treasures," 11 Nov. 2020

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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Learn More about tamper

Time Traveler for tamper

Time Traveler

The first known use of tamper was in 1567

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Statistics for tamper

Last Updated

20 Jan 2021

Cite this Entry

“Tamper.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tamper. Accessed 24 Jan. 2021.

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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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