profuse sweating; sweating like a waterfall
Slang term for sweating heavily, often used in online or casual contexts to describe extreme nervousness, embarrassment, or physical exertion. The kanji 滝 (waterfall) vividly conveys the image of sweat pouring down.
面接で緊張して滝汗をかいた。
I was so nervous during the interview that I was sweating like a waterfall.
夏の屋外作業は滝汗が止まらない。
Working outdoors in summer, the profuse sweating just won't stop.
Compound of 滝 (waterfall) and 汗 (sweat), literally 'waterfall sweat'. A modern slang coinage, likely from internet or manga usage, describing sweat flowing like a waterfall.