اللهم

Extended form of الله‎ (allāh). The origin of the م‎ (m) is unknown. Theories include a connection with مَا‎ (mā), or a borrowing from Hebrew אלהים‎ (“elohim”), where the final -m is a majestic plural ending. The form is first attested in the Quran (3:26, 5:114, 8:32, 10:10, 39:46).

اللّٰهُمَّ • (allāhumma)

1. God, O God; vocative form of الله‎ (allāh) used in invocations, oaths, etc.
   • 7th century CE, 'The Quran'‎:

     ‏قُلِ ٱللَّهُمَّ مَالِكَ الْمُلْكِ تُؤْتِي الْمُلْكَ مَنْ تَشَاءُ وَتَنْزِعُ الْمُلْكَ مِمَّنْ تَشَاءُ وَتُعِزُّ مَنْ تَشَاءُ وَتُذِلُّ مَنْ تَشَاءُ بِيَدِكَ الْخَيْرُ إِنَّكَ عَلَىٰ كُلِّ شَيْءٍ قَدِيرٌ‎

     quli l-lahumma mālika l-mulki tuʾtī l-mulka man tašāʾu watanziʿu l-mulka mimman tašāʾu watuʿizzu man tašāʾu watuḏillu man tašāʾu biyadika l-ḵayru ʾinnaka ʿalā kulli šayʾin qadīrun

     O God, Lord of all dominion! Thou grantest dominion unto whom Thou willest, and takest away dominion from whom Thou willest and abasest whom Thou willest. In Thy hand is all good. Verily, Thou hast the power to will anything.

   • 7th century CE, 'The Quran'‎:

     ‏وَإِذْ قَالُوا۟ ٱللَّهُمَّ إِنْ كَانَ هَٰذَا هُوَ الْحَقَّ مِنْ عِنْدِكَ فَأَمْطِرْ عَلَيْنَا حِجَارَةً مِنَ السَّمَاءِ أَوِ ٱئْتِنَا بِعَذَابٍ أَلِيمٍ‎

     And, lo, they would say, "O God! If this be indeed the truth from Thee, then rain down upon us stones from the skies, or inflict grievous suffering on us!"

• يَا أَللّٰهُ‎
• يَا رَبُّ‎ (yā rabbu)