Lit. “The surely Impending.” The title of the LXIXth Surah of the Qur’an, in which the word occurs in the opening verse: “The inevitable! (al-Haqqutu!). What is the inevitable?” The word is understood by all commentators to mean the Day of Resurrection and Judgement. It does not occur in any other portion of the Qur’an.
Based on Hughes, Dictionary of Islam