water off a duck's back
English edit
Etymology edit
From the idea that water rolls easily off a duck's back and does not penetrate the duck's feathers.
Noun edit
water off a duck's back (uncountable)
- Something potentially harmful or hurtful, such as criticism or insult, that nevertheless has no effect or impact on the target.
- She's always going on at him about something, but to him it's all water off a duck's back.
Usage notes edit
Often in the expression like water off a duck's back.