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tool (tl)
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n.
1. A device, such as a saw, shovel, or drill, used to perform or facilitate manual or mechanical work.
2.
a. A machine, such as a lathe, used to cut and shape machine parts or other objects.
b. The cutting part of such a machine.
3. Something regarded as necessary to the carrying out of one's occupation or profession: Words are the tools of our trade.
4. Something used in the performance of an operation; an instrument: "Modern democracies have the fiscal and monetary tools ... to end chronic slumps and galloping inflations" (Paul A. Samuelson).
5. Vulgar Slang The penis.
6. A person used to carry out the designs of another; a dupe.
7.
a. A bookbinder's hand stamp.
b. A design impressed on a book cover by such a stamp.
8. Computers A utility program.
v. tooled, tool·ing, tools
v.tr.
1. To form, work, or decorate with a tool.
2. To ornament (a book cover) with a bookbinder's tool.
3. Slang To drive (a vehicle): tooled the car at 80 miles an hour.
v.intr.
1. To work with a tool.
2. Slang To drive or ride in a vehicle: tooled up and down the roads.
Phrasal Verb:
tool up
To provide an industry or a factory with machinery and tools suitable for a particular job.

[Middle English, from Old English tōl, possibly from Old Norse.]
(click for a larger image)
tool
tooled leather

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 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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