pivotal
US /ˈpɪv.ə.t̬əl/
UK /ˈpɪv.ə.t̬əl/

1.
crucial, fundamental, essencial
of crucial importance in relation to the development or success of something else
:
•
The discovery of penicillin was a pivotal moment in medicine.
A descoberta da penicilina foi um momento crucial na medicina.
•
Her role in the project was absolutely pivotal.
O papel dela no projeto foi absolutamente fundamental.