"汗下"可以翻譯為 **"sweating profusely"** 或 **"breaking into a cold sweat"**，具體語境如下：

1. **字面意思（因熱/運動出汗）**：
- "Sweating heavily" / "Dripping with sweat"
- 例：他跑完馬拉松后汗下如雨。
*He was sweating profusely after running the marathon.*

2. **比喻義（因緊張、羞愧等冒冷汗）**：
- "Breaking into a cold sweat"
- 例：被當眾批評時，他頓時汗下。
*When criticized publicly, he broke into a cold sweat.*

3. **中醫術語（發汗療法）**：
- "Induced sweating"（作為治療手段的出汗）

根據上下文選擇最貼切的譯法即可。