Cabeça Oca (Empty Head; Cabeça-Head, Oca-Empty) - It's a brazilian way of calling those people who don't know or don't understand what themselves are doing. '
Cabeça Oca' - It's similar to 'burro' (dumb), but 'cabeça oca' has a slight intensity so the target person don't get offended by.

Cabeça Oca - These words are used together in this form to name one or more fellows. When a person lack information and/or don't know how to do something obvious, you call him 'Cabeça Oca'. It's good to be familiar with the person you're calling this way.

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