Bountiful, a.
1. Free in giving; liberal in bestowing gifts and favors. God, the bountiful Author of our being. Locke.
2. Plentiful; abundant; as, a bountiful supply of food.
Syn. -- Liberal; munificent; generous; bounteous. -- Boun"ti*ful*ly, adv. -- Boun"ti*ful*ness, n.
Shades of meaning
Fernald has no entry of its own for bountiful; he lists it under generous, plentiful.
Where he writes about it:
That is ample which gives a safe, but not a large, margin beyond a given demand; that is abundant, affluent, bountiful, liberal, plentiful, which is largely in excess of manifest need. — from plentiful