1. Not following a regular, predictable, or usual pattern; inconsistent and unpredictable
His erratic behavior made it difficult for his colleagues to work with him.
Seu comportamento errático dificultava o trabalho com seus colegas.
2. Moving or functioning in an unpredictable way; deviating from the norm
The car's erratic performance suggested engine problems.
O desempenho errático do carro sugeria problemas no motor.
3. In geology, referring to a rock that has been transported far from its source by glacial action
The erratic boulder was deposited by a glacier millions of years ago.
A rocha errática foi depositada por uma geleira há milhões de anos.