General Brazilian
desacelerar; diminuir a velocidade; abrandar
Most common usage across Brazil
Rio de Janeiro
desacelerar; ir mais devagar
Colloquial preference for simpler terms
São Paulo
diminuir a velocidade; desacelerar
Business and formal contexts preferred
Portugal
abrandar; desacelerar; diminuir o ritmo
'Abrandar' is more commonly used in Portugal