الأَعْلَى

A word in the Arabic language will either be 1) a verb or 2) a noun or 3) a particle – الأَعْلَى is a noun

A noun may either be 1) Definite or indefinite 2) Masculine or feminine 3) Singular, dual or plural 4) Nominative, accusative or genitive

الأَعْلَى is the natural state of this definite noun and it remains to الأَعْلَى even though it is in the genitive case due to: 1) a preposition that precedes it or 2) a possessed noun that precedes it or 3) it’s a noun of dependent declension a) نَعْتٌ / صِفَطٌ adjectives b) التَّوْكِيْدُ emphatic c) المَعْطُوْفٌ conjunction d) البَدَلُ synonym

The final letter in this nominal pattern الأَعْلَى is a weak letter (ي) weak letters do not show their endings, their endings have to be estimated (deduced by reason)

The great

To be high, elevated, lofty, exalted, ascend, overcome, be proud, be upon, be over, go up, rise in rank or dignity, raise, take up, mount, overtop

الْمَعْرِفَةُمُفْرَدٌمُذَكَّرٌمَجْرُوْرٌع ل وبَاب سَمِعَعَلِيَ يَعْلَىأَفْعَلُاسْمٌالْاِسْمُ التَّفْضِيْلُ
DefiniteSingularMasculineGenitiveRootExalted / HighسPatternNounSuperlative noun
Surah/Below are the 3 verses in the holy Quran containing the genitive nounالأَعْلَى
Verse 
  
79-24and said, “I am your lord, the high”فَقَالَ أَنَاْ رَبُّكُمُ الأَعْلَى
87-1Glorify the name of your Lord, the Most-High,سَبِّحِ اسْمَ رَبِّكَ الأَعْلَى
92-20except to seek the Countenance of his Lord, the Most Highإِلَّا ابْتِغَآءَ وَجْهِ رَبِّهِ الْأَعْلَى