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tam·per 1 (tămpər)
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v. tam·pered, tam·per·ing, tam·pers
v.intr.
1.
a. To interfere in a harmful or disruptive manner; meddle: was worried the editor would tamper with her text.
b. To make alterations or adjustments, especially secretly so as to subvert an intended purpose or function: tamper with a lock; discovered that the brakes had been tampered with.
c. To engage in improper or secret actions, as in an effort to influence an outcome: tamper with evidence; tamper with a jury.
2. To tinker rashly or foolishly: "The ability of chemists to create new drugs from natural compounds raises an old argument about whether human beings should tamper with nature" (Andrew Weil).
v.tr.
To alter improperly.

[Probably alteration of TEMPER.]

tamper·er n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
tamp·er 2 (tămpər)
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n.
A neutron reflector in an atomic bomb that also delays the expansion of the exploding material, making possible a longer-lasting, more energetic, and more efficient explosion.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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