HOUR, The. Arabic as-Sa’ah الساعة
A term frequently used in the Qur’an for the Day of Judgement.
Surah vi. 31: “When the hour comes suddenly upon them.”
Surah vii. 186: “They will ask you about the hour for what time it is fixed.”
Surah xv. 85: “Verily the hour is surely coming.”
Surah xvi. 79: “Nor is the matter of the hour aught but as the twinkling of an eye, or nigher still.”
Surah xxii. 1: “Verily the earthquake of the hour is their promised time! And the hour is most severe and bitter.”

Based on Hughes, Dictionary of Islam