Origin: 1715–25; < G Deferveszenz < L dēfervēsc(ent-) (s. of dēfervēscēns, prp. of dēfervēscere, equiv. to dē-de+ fervēscere to begin to boil) + -ence; see effervescent
de·fer·ves·cence (dē'fər-věs'əns) n. 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 Indo-European roots.] de'fer·vesce' (-věs') v., de'fer·ves'cent adj.