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 Agriculture Department has probed allegations of tampering with scientific reports on climate change. NBC News, "Democrats question why DOJ inspector general isn't investigating Trump's attorneys general," 27 Nov. 2019 Wanda Rivera, the family matriarch, is accused of tampering with evidence and lying to investigators. Katie Rice, orlandosentinel.com, "Who are the Riveras, the family implicated in the killing of St. Cloud mother Nicole Montalvo? | Special report," 27 Nov. 2019 Bryant is charged with one count of tampering with a government record. St. John Barned-smith And Keri Blakinger, Houston Chronicle, "Gerald Goines, ex-cop at center of Harding Street drug raid, arrested by FBI," 20 Nov. 2019 Jennifer was reported missing by her husband last Tuesday night — a day before his initial arrest on a charge of tampering with physical evidence. Jeff Truesdell, PEOPLE.com, "Body Found in Search for Mo. Woman — and Husband Is Charged After Blood-Soaked Carpet Spotted," 19 Nov. 2019 Frazee, 33, faces eight charges: two counts of first-degree murder, three counts of solicitation to commit murder, two counts of a crime of violence and one count of tampering with a body. Jack Hannah And Darran Simon, CNN, "Jury deliberations begin in the Patrick Frazee murder trial," 18 Nov. 2019 He was also found guilty of tampering with a witness, radio personality Randy Credico, pressing him not to cooperate with a congressional investigation that involved Stone. CBS News, "Roger Stone, former Trump campaign adviser, found guilty on all charges," 15 Nov. 2019 In addition to the misdemeanor, Dingman is accused of tampering with evidence, a felony punishable by up to five years. Rafael Olmeda, sun-sentinel.com, "In a rare move, cop faces a criminal leak investigation," 30 Oct. 2019 Sarvis has been charged with one count of murder and one count of tampering with physical evidence. Billy Kobin, The Courier-Journal, "Louisville police: Woman is charged with murder in Klondike neighborhood death," 19 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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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

4 Dec 2019

Cite this Entry

“Tamper.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/tamperproof?pronunciation&lang=en_us&dir=t&file=tamper04. Accessed 11 December 2019.

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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).


heavy with or as if with moisture

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