The term “whatnot,” used to refer to a small, usually inconsequential object, dates from 1540. Ornaments and other decorations may be referred to collectively with this term, and in 1808, the term began to describe the piece of furniture used to hold various items as well. A number of furniture designs fall under this general category, but a typical whatnot has open shelves, often supported by decoratively carved pillars, and it is designed to display objects. The open shelved display has, of course, been around since long before 1808, and has been referred to by other names including the French etagere.
In order to be considered a true whatnot, a shelving unit must be clearly designed for display purposes, and in general will not accommodate books or other heavy items. The open shelves allow a clear view of all the objects on display, which are usually artfully arranged to create a pleasing visual field. The bottom of the unit may include a small drawer, and it may also be on casters so that it can be easily moved. The support columns are generally very spindly and thin, suggesting an air of delicacy and refinement.
Often, a whatnot is designed to fill a corner or another awkward space. Triangular whatnots designed to fill corners are very common, and frequently feature shelves in graduated sizes, terminating with a very small, highly carved ornamental shelf. Square or rectangular whatnots tend not to have graduated shelving, but they still have highly ornamental support columns. It's important to distinguish this type of furniture from a display case, which usually has closing doors designed to secure items inside.
Many antique stores refurbish and sell whatnots, especially in England. They are also available new, and some designers have developed sleek modern updates on the traditional designs for more contemporary interior decor. Most designs use wood, although plastic and metal fabrications can be found in modern design, and the furniture is usually very lightweight. Residents of earthquake prone areas may want to avoid displaying valuable breakables on a whatnot, unless they plan on securing the items to the shelves or purchasing a lipped whatnot so that ornaments cannot fall off. Families with pets and small children should probably avoid the purchase of these pieces altogether, as the delicate furniture does not do well with rough usage.