Physically overheated — a real heatwave, a stuffy room, or exercising hard — but equally popular figuratively for describing an attractive person or an intensely 'hot' (in either sense) situation. Added in Unicode 11.0 (2018) alongside its cold-face twin, giving temperature-based emotion its own dedicated pair.
Keywords: dying, face, feverish, heat, hot, panting, red-faced, stroke, sweating, tongue