Expressions (phrases, clauses, etc.), Ichidan verb
to sprinkle water on (something); to spray water on; to splash water on; to squirt water on
その少年は、私達が彼の顔に水をかけると、意識を取り戻した。The boy came around when we threw water on his face. to hinder; to hamper; to stifle; to throw cold water on
Idiomatic expressionsee 水をさす
Also written 水を掛ける【みずをかける】