subfebrile
/sʌbˈfɛbraɪl/Definitions
1. adjective
slightly above or below normal body temperature, typically just below 98.6°F (37°C); having a low-grade fever
“The patient’s subfebrile temperature indicated that she was recovering from the illness.”
2. noun
a condition of having a slightly raised body temperature
“The doctor diagnosed the patient with a subfebrile condition, recommending rest and hydration.”