Al-Wasi'

The root. Al-Wasi comes from w-s-ʿ, the root behind saʿa (breadth, room) and wusʿ (capacity, means — the same root behind the Quranic phrase that no soul is burdened beyond its wusʿ, its capacity). What the root carries is spaciousness that leaves nothing cramped or short — enough room for whatever needs to fit. Al-Wasi is shaped as a plain adjective, naming this breadth as a settled attribute of His giving, knowledge, and mercy alike.

What it means here. Al-Wasi is read on three connected fronts: His provision is broad enough that no one's need exhausts it, His knowledge is broad enough that nothing escapes it, and His mercy is broad enough to reach what human mercy cannot. It is almost always paired with Al-Alim in the Quran, the two together making a single point — that the breadth named by Al-Wasi is not vague or unfocused but exact, matched by a knowledge that reaches every particular within it.

Where it is met. Al-Wasi is paired with Al-Alim across Surah Al-Baqara, appearing after verses on the direction of prayer, on charity given quietly, and on lending to Allah with a goodly loan multiplied without limit. Surah An-Nisa uses the same word of His encompassing mercy, and Surah An-Nur pairs it with Al-Alim again in a verse urging the poor to marry, trusting Allah to provide from His vast bounty.