"Fancy" plywoods, the stuff used in cabinet making, aren't solid hardwood. They have a thin layer of hardwood veneer over some sort of substrate. The strongest and most expensive are VC, which means "veneer core." It has an inner core of solid pieces of wood laid at 90* to each other like any old plywood. Usually the "fancy" stuff has more layers than box store stuff though, like 7 or 9 layers for 3/4", sometimes 11.

Not all circumstances call for the strength or expense of VC ply, so "fancy" hardwood veneer also comes on chip core (CC) or MDF core, (MDF). CC is like melamine, but with hardwood veneer instead of plastic. It's a bit of a bummer to work with because usually the veneer they put on it is so thin you can't sand it, and it tends to telegraph the chips. Nowadays most artisan quality hand-done veneer work, like tables, are done on MDF because MDF is more stable than even VC plywood, so MDF is a good choice if you don't need maximum strength. A lot of thinner plys, like 1/8 and 3/16 only come in MDF core.

You see the same sort of thing in marine plywood, too. They make "teak" and "Teak and holly" plywood that is simply a veneer over a luan core.

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