Al-Qahhar — The All-Prevailing One
الْقَهَّارُ
Name 15 of the ninety-nine. The Dominant, The One who has the perfect Power
Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ is Al-Qahhar (in Arabic: ٱلْقَهَّارُ), meaning the one who prevails over all creation.
The root
From the root qaf-ha-ra (ق ه ر), which has the following classical Arabic connotations: to overcome, conquer to overpower, master to dominate over, prevail to subdue, subjugate, to compel against one's wishes.
Reflection
In using this beautiful name of Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ in your supplication, you can have the assurance that the most powerful is with you. If Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ is with you, just as He was with Prophet Musa (as) when he stood against Firawn, or when Prophet Muhammad ﷺ was being persecuted by the Meccans, or when Prophet Dawud (as) fought and won the battle against Jalut, then nothing can overpower you.
org/surah-imran/ayat-160/)) Du'a with this name: لا إِلـهَ إِلاّ اللهُ الـواحِدُ القَهّـار رَبُّ السَّـمواتِ وَالأرْضِ وَما بَيْـنَهـما العَزيـزُ الغَـفّار La ilaha illallah al-Wahidul-Qahhar, Rabbus-samawati wa 'l-ardi wa ma baynahuma al-`Azīzul-Ghaffar.
Where it appears
[1] Hisn al-Muslim 112