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through (thr)
1. In one side and out the opposite or another side of: went through the tunnel.
2. Among or between; in the midst of: a walk through the flowers.
3. By way of: climbed in through the window.
a. By the means or agency of: bought the antique vase through a dealer.
b. Into and out of the handling, care, processing, modification, or consideration of: Her application went through our office. Run the figures through the computer.
5. Here and there in; around: a tour through France.
6. From the beginning to the end of: stayed up through the night.
7. At or to the end of; done or finished with, especially successfully: We are through the initial testing period.
8. Up to and including: a play that runs through December; a volume that covers A through D.
9. Past and without stopping for: drove through a red light.
10. Because of; on account of: She succeeded through hard work. He declined the honor through modesty.
1. From one end or side to another or an opposite end or side: opened the door and went through.
2. From beginning to end; completely: I read the article once through.
3. Throughout the whole extent or thickness; thoroughly: warmed the leftovers clear through; got soaked through in the rain; a letter that was shot through with the writer's personality.
4. Over the total distance; all the way: drove through to their final destination.
5. To a conclusion or an accomplishment: see a matter through.
1. Allowing continuous passage; unobstructed: a through street.
a. Affording transportation to a destination with few or no stops and no transfers: a through bus; a through ticket.
b. Continuing on a highway without exiting: through traffic; through lanes.
3. Passing or extending from one end, side, or surface to another: a through beam.
4. Having finished; at completion: She was through with the project.
5. Having no further concern, dealings, or connection: I'm through with him.
a. Having no more use, value, or potential; washed-up: That swimmer is through as an athlete.
b. Doomed to death or destruction.
through and through
1. In every part; throughout: wet through and through.
2. In every aspect; completely: a success through and through.

[Middle English thurh, through, from Old English thurh; see terə-2 in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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.