slacken
US /ˈslæk.ən/
UK /ˈslæk.ən/

1.
aflojar, disminuir, relajar
make or become less active or intense
:
•
The rain began to slacken.
La lluvia comenzó a disminuir.
•
He needs to slacken his pace if he wants to finish the marathon.
Necesita disminuir su ritmo si quiere terminar el maratón.