КАК РЫБЕ ЗОНТИК

• КАК РЫБКЕ <РЫБЕ> ЗОНТИК нужен highly coll

[как + NP; these forms only; adv (neg intensif)]

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⇒ completely unnecessary, of no use to s.o.:

- (be as much use to s.o.) as an umbrella to a duck;

- (need sth.) like <as> a duck needs an umbrella.