This noun denotes heat or warmth, whether from the sun, fire, or fever. Classical usage applied it to hot weather, feverish heat, and thermal energy. Luke uses it in Acts to describe the heat that drove a viper from the firewood Paul was gathering. The term emphasizes the physical sensation and effect of heat. It could describe both beneficial warmth and dangerous, burning heat. Greek medical writers used it for fevers and inflammatory conditions. The word captures heat as both a natural phenomenon and a potential danger.