Vegetables are plants grown for their vegetative parts, such as leaves or stems. However, some "vegetables" are actually flower parts, and many fruits are referred to as vegetables as well.
Vegetable is a culinary term which may be applied to any part of an herbaceous plant that humans eat whole or in part is a vegetable, except for culinary fruit, grains, nuts, herbs, and spices. Mushrooms are also commonly considered vegetables, though of course these are not true plants.