Ma'anar ƙamus na "zazzabi na jiki" shine zafin jiki na cikin halitta mai rai, yawanci yana nufin yanayin zafin jikin mutum ko dabba. A cikin mutane, matsakaicin yanayin zafin jiki na yau da kullun yana kusa da 98.6 Fahrenheit (digiri 37 Celsius). Koyaya, wannan na iya bambanta dan kadan dangane da dalilai kamar shekaru, jima'i, matakin aiki, da lokacin rana. Yawan zafin jiki ana auna shi da ma'aunin zafi da sanyio da aka sanya a ƙarƙashin harshe, a cikin kunne, ko kuma a kai tsaye.