1. An effect, feeling, or image retained as a consequence of experience: Seeing the glacier made a big impression on us.
2. A vague notion, remembrance, or belief: I have the impression that we have met once before.
3. A mark produced on a surface by pressure.
4. The act or process of impressing: The impression of the company's name in the products is done by machine.
a. All the copies of a publication printed at one time from the same set of type.
b. A single copy of such a printing.
6. A humorous imitation of the voice and mannerisms of a famous person.
7. An initial or single coat of color or paint.
8. Dentistry An imprint of the teeth and surrounding tissues, formed with a plastic material that hardens into a mold for use in making dentures, inlays, or plastic models.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 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:
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.