noun
water filter; strainer; colander
A kitchen tool for straining water from foods like noodles or vegetables; essentially a colander or strainer.
茹でたパスタを水漉しにあける。
I drain the boiled pasta into a colander.
野菜を洗った後、水漉しで水を切る。
After washing the vegetables, I drain the water with a strainer.
ざる is a general flat sieve or basket, often bamboo or plastic, while 水漉し specifically emphasizes straining water and is typically a deeper bowl-shaped colander.
漉し器 is a broader term for any straining device (e.g., a sieve or filter), while 水漉し is specifically for water and often implies a colander.
Compound of 水 (mizu, 'water') and 漉し (koshi, the noun form of 漉す 'to filter, strain'). The spelling 漉し is standard for this meaning.