De`fer*ves"cence (?), De`fer*ves"cency (?), n. [L. defervescere to grow cool.]
1.
A subsiding from a state of ebullition; loss of heat; lukewarmness.
A defervescency in holy actions.
Jer. Taylor.
2. Med.
The subsidence of a febrile process; as, the stage of defervescence in pneumonia.
© Webster 1913.