1. Substances that can flow and have no fixed shape, such as liquids or gases
Water and oil are different types of fluids.
Água e óleo são diferentes tipos de fluidos.
2. In medicine, body liquids such as blood, urine, or cerebrospinal fluid
The doctor ordered tests on the patient's fluids.
O médico pediu testes nos fluidos do paciente.
3. Liquids used in machinery or vehicles for lubrication or cooling
Check the brake fluids in your car regularly.
Verifique regularmente os fluidos de freio do seu carro.