to poke the bear, to provoke someone
Não cutuca a onça com vara curta, a Maria está sem paciência hoje!
Don't poke the bear, Maria is out of patience today!
The expression cutucar a onça com vara curta ("to poke the jaguar with a short stick") is a Brazilian saying whose imagery goes back to the colonial era, when settlers and hunters had to deal with the jaguar (onça), a powerful and unpredictable predator. Prodding such an animal with a stick too short to keep a safe distance was suicidally reckless.
Source: Correio do Estado.
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