The abatement of a fever.
[From Latin dēfervēscēns, dēfervēscent-, present participle of dēfervēscere, to stop boiling, cool off : dē-, de- + fervēscere, to grow hot, inchoative of fervēre, to be hot, boil; see bhreu- in the Appendix of Indo-European roots.]
de′fer·vesce (-vĕs) v.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 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.