wariacki in inglese:

It would be foolhardy to ignore these warnings.

1) The brave man, if he be compared with the coward, seems foolhardy; and, if with the foolhardy man, seems a coward. 2) Hatred is blind, anger is foolhardy, and he who pours out vengeance risks having to drink a bitter draft. (Alexandre Dumas)

Children love clowns because their wacky clothes and antics make them laugh.

You're a wacky guy.

Have you heard of that wacky fashion website?

By inference, their inventor is sometimes regarded as a wacky innovator who was perhaps out of touch with reality. But Fuller’s career involved a great deal more than domes.