The One who is supremely great. The One who is greater than all of creation.
“He is Allah than Whom there is La ilaha illa Huwa (none has the right to be worshipped but He) the King, the Holy, the One Free from all defects, the Giver of security, the Watcher over His creatures, the All-Mighty, the Compeller, the Supreme. Glory be to Allah! (High is He) above all that they associate as partners with Him.”
(59:23) The Holy Quran
From the root k-b-r with the classical Arabic connotations: to be great in size, rank or dignity to be great in size, to be vast, formidable to be great in age, oldest to be great in dignity, noble, majestic.