1. To react or answer to something based on natural, intuitive impulses rather than conscious thought or deliberation
When she saw the child falling, she responded by instinct and caught him before he hit the ground.
Quando ela viu a criança caindo, respondeu por instinto e o pegou antes de bater no chão.
2. To act automatically without rational analysis, following inherent behavioral patterns
The athlete responded by instinct during the critical moment, executing the perfect play.
O atleta respondeu por instinto no momento crítico, executando o jogo perfeito.