Flour based foods that are chemically leavened, especially muffins and items like banana breads
In the most technical sense, a quickbread is any flour based item leavened with chemical leavening as opposed to being (slowly) leavened by yeast.
Most quickbreads are baked in an oven, although some may be griddled, fried, or deep fried.
The most typical quickbreads include things like muffins, banana bread, and irish soda bread. Less typical quickbreads include biscuits and scones.