火热
huǒ rè · HSK 7
fervent
🔥 火 (fire) + 热 (hot) = fiery, burning hot, fervent
Both characters carry heat: 火 is fire, 热 is hot. Stacked together they push past literal temperature into figurative heat — passion, fervor, an ardent or intense mood.
火 — pictograph of flames rising
火 is a pictograph showing flames rising upward from a fire, with the central stroke as the main blaze and the side strokes as sparks. The ancient oracle bone form looked even more clearly like a burning flame. It still means 'fire' today and serves as a common radical in characters related to heat, burning, or cooking.
热 — 执 zhí (phonetic) + 灬 fire radical
热 is a semantic-phonetic compound: the bottom 灬 (a variant of 火 'fire') gives the meaning of heat, while 执 on top supplies the sound. Originally written 熱, it depicted fire below a phonetic element, and the meaning naturally extended from physical heat to 'hot' weather and 'enthusiastic' feelings.