tamper

1 of 2

verb

tam·​per ˈtam-pər 

tampered; tampering ˈtam-p(ə-)riŋ  ; tampers

intransitive verb

1

a

: to interfere so as to weaken or change for the worse

—used with with

did 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

2

a

: 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 with

These 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

tamperer

ˈtam-pər-ər 

noun

plural tamperers

tamperproof

ˈtam-pər-ˌprüf 

adjective

tamper

2 of 2

noun

tamp·​er ˈtam-pər 

plural tampers

: 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

Synonyms

Verb

• diddle (with)
• fiddle (with)
• fool (with)
• mess (with)
• monkey (with)
• play (with)
• tinker (with)
• toy (with)
• twiddle (with)

Examples of tamper in a Sentence

Verb

someone has tampered with my computer files

Recent Examples on the Web

Verb

Police found Oddo at a Mount Pleasant motel on June 2 and charged him with murder and evidence tampering. —Christina Coulter, People.com, 9 June 2025

Blockchain technology has prevented cyberattacks, fraud and data tampering, delivering enhanced security, transparency and operational trust across the insurance value chain. —Arpna Aggarwal, Forbes.com, 29 May 2025

Noun

If your seeded zone is small, lightly tamp the area with your shoes or a tamper to press the seed firmly against the soil. 4. —Megan Hughes, Better Homes & Gardens, 17 Apr. 2025

Most ballot drop boxes are tamper proof, bolted to the ground, under 24-hour surveillance, and include fire suppression systems. —Peter Charalambous, ABC News, 29 Oct. 2024

Word History

Etymology

Verb

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

First Known Use

Verb

1567, in the meaning defined at sense 2

Noun

circa 1864, in the meaning defined above

Phrases Containing tamper

• tamper with

Rhymes for tamper

• camper
• damper
• hamper
• pamper
• scamper
• stamper

Kids Definition

tamper

verb

tam·​per ˈtam-pər 

tampered; tampering -p(ə-)riŋ 

1

: to interfere in a secret or wrongful way

2

a

: to interfere so as to cause a weakening or change for the worse

b

: to try foolish or dangerous experiments

Legal Definition

tamper

intransitive verb

tam·​per

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