发热

• Pinyin: fā rè
• Hanzi breakdown: 发 = 弓 + 殳 — to emit, produce; 热 = 执 (to grasp/hold) + 灬 (fire radical) — holding fire, generating intense heat

Meaning

To have a fever; to generate heat. Also figurative: (of the mind) to become overheated with excitement, causing poor judgement.

Medical sense: body temperature elevated above normal. Figurative sense: 头脑发热 (head overheating) — acting impulsively or making irrational decisions driven by excitement or enthusiasm. Both senses are widely used.

Examples

1. 孩子昨晚开始发热，体温一度升至三十九度二，父母立即带他去最近的儿科急诊就医。 The child developed a fever last night, and his temperature rose as high as 39.2°C, so his parents immediately took him to the nearest pediatric ER.
2. 许多投资者在市场极度乐观的氛围中头脑发热，做出了不符合自身风险承受能力的仓促决策。 In an extremely optimistic market atmosphere, many investors get carried away and make rushed decisions that don’t match their own risk tolerance.
3. 这种新型散热材料在高负荷运行状态下能有效防止芯片发热，延长设备的使用寿命并降低故障率。 This new heat-dissipation material can effectively prevent chips from overheating under high-load operation, extending equipment life and reducing failure rates.

Usage Guide

Context: medical, everyday, finance, technology

Tone: neutral

Do Say

• 患者持续发热超过四十八小时，医生怀疑存在细菌感染。(The patient had a fever for over forty-eight hours, so the doctor suspected a bacterial infection.)
• 创业热潮中，不少年轻人头脑发热，在没有充分市场调研和财务规划的情况下贸然辞职创业，最终因资金链断裂而被迫关闭公司，损失惨重。(In the wave of entrepreneurial enthusiasm, many young people's heads overheated; they rashly quit their jobs to start businesses without adequate market research or financial planning, and ultimately were forced to shut their companies due to broken cash flows, suffering severe losses.)

Don't Say

• 我发热了感冒 — 发热 is typically a symptom, not a cause; say 我感冒了，一直在发热 or 我因为感冒而发热 for the correct causal relationship

Origin & History

发 (to give rise to/emit) + 热 (heat/fever) — to produce or emit heat; to run a fever

Cultural Context

Generation: All ages

Social background: Universal