From Middle High German vieber, from Old High German fiebar, from Latin febris (“fever”), from Proto-Indo-European *dʰegʷʰ- (“to burn”). The early loanword (attested 830) gradually displaced native Ritte, from Proto-Germanic *hriþiz (literally “trembling”).
Cognate with Old English fefor (whence modern English fever), though this is likely an independant borrowing. From High German the word emanated into Middle Low German, and thence further into the North Germanic languages, whereas Dutch has not adopted it.
Fieber n (genitive Fiebers, plural Fieber)
- “Fieber” in Duden online