1. A short period of peace, calmness, or absence of disturbance
After the storm, there was a brief tranquility before the next wave hit.
Após a tempestade, houve uma tranquilidade breve antes da próxima onda chegar.
2. A momentary state of quiet or serenity that is short-lived
The brief tranquility of the morning was soon interrupted by traffic noise.
A tranquilidade breve da manhã foi logo interrompida pelo barulho do trânsito.