profuse sweat; sweat pouring off
Almost always used in the set phrases 汗水たらして or 汗水流して, meaning 'dripping with sweat' or 'working up a sweat'. Not used as a standalone noun in modern Japanese.
See also: 汗水流す
He is working hard, dripping with sweat.
The results of practicing while drenched in sweat paid off.
Standard kanji spelling; common in set phrases.
Compound of 汗 (あせ, 'sweat') and 水 (みず, 'water'), literally 'sweat water'. The reading あせみず is a straightforward combination.