zero hour
US /ˈzɪroʊ ˈaʊər/
UK /ˈzɪroʊ ˈaʊər/

1.
waktu sifar, masa permulaan
the time at which a planned operation or event is scheduled to begin
:
•
The troops were ready for zero hour, awaiting the command to advance.
Pasukan bersedia untuk waktu sifar, menanti arahan untuk mara.
•
The launch countdown began, signaling that zero hour was approaching.
Kira detik pelancaran bermula, menandakan waktu sifar semakin hampir.