v. swel·tered, swel·ter·ing, swel·ters
To suffer from oppressive heat.
Archaic To exude (venom, for example).
A condition of oppressive heat.
[Middle English swelteren, frequentative of swelten, to faint from heat, from Old English sweltan, to perish.]
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:
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.