Mushrooms

Yes.

And I forgot to add, tomatoes are a fruit.

So what is a vegetable???

Fruits are the part of the plant that bears seeds. Nuts are the seeds themselves. Except for legumes which......? Hmmm. Mushrooms are fungi which are a critter all-together different: not quite plant, not quite animal (I typed human - oy!).

Anything that isn't a mineral or animal is a veggie. *nods*

I'm with fishin'--specially when it grows in dirt and you don't need no hammer to break it loose.

We refer to carrots, beets and potatoes as root vegetables. But legumes (peas, beans) are also vegetables. A tomato, as you say, is a fruit for botanical classification purposes. But it's a veggie for gastronomical purposes. As littlek has rightly said, nuts are seeds and fruit are the containers of seeds. But what are we talking about here -- botany or gastronomy? Mushrooms are fungi, yes, but they are used as vegetables in cooking. The two questions -- how are things classified for scientific purposes and how they are sorted as foodstuffs -- are two entirely different subjects.