The word as it is recited in the Quran: Mahmoud Khalil Al-Hussary, Ar-Ra’d 13:7.
Hadi in Islam
The word occurs in the Quran for Allah: “Your Lord suffices as a guide (hadiyan) and a helper” (25:31), and for the messengers: “You are only a warner, and for every people there is a guide (had)” (13:7).
Meaning of the name Hadi
Hadi is the active participle of hada, “to guide, to set on the right path” (root h-d-y, that of huda and hidaya): the guide. Al-Hadi, “the Guide”, appears in the traditional list of the ninety-nine names of Allah; borne by a man, the word keeps its human sense. Hédi is the Tunisian form, Hadi that of the Middle East and Iran.
And so those who were given knowledge may know that it is the truth from your Lord and [therefore] believe in it, and their hearts humbly submit to it. And indeed is Allāh the Guide of those who have believed to a straight path.
Then is He who is a maintainer of every soul, [knowing] what it has earned, [like any other]? But to Allāh they have attributed partners. Say, "Name them. Or do you inform Him of that which He knows not upon the earth or of what is apparent [i.e., alleged] of speech?" Rather, their [own] plan has been made attractive to those who disbelieve, and they have been averted from the way. And whomever Allāh sends astray - there will be for him no guide.
And you cannot guide the blind away from their error. You will only make hear those who believe in Our verses so they are Muslims [in submission to Allāh].