1. The crashing or booming sound produced by rapidly expanding air along the path of the electrical discharge of lightning.
2. A sound that resembles or suggests thunder.
v. thun·dered, thun·der·ing, thun·ders
1. To produce thunder.
2. To produce sounds like thunder.
3. To move while making a loud noise: The express train thundered past us.
4. To utter loud, vociferous remarks or threats.
To express violently, commandingly, or angrily; roar.
[Middle English thonder, from Old English thunor; see (s)tenə- in the Appendix of Indo-European roots.]
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.