A staddle is a kind of support that keeps things off the ground in order to protect them, specifically, a leg- or post-like support, especially one used in an agricultural setting. The staddle is specifically the support, and is not used to refer to any sort of any container that might be on top of the support.
Staddles are best known as supports for barns and other outbuildings (including storage barns, granaries and game larders); while they may come in any number of forms, the most common form is a stout pillar with a wide cap, the combination looking like a large mushroom. The cap keeps rodents from climbing up the staddles and into the barn.
While a staddle can be made from any substance, they are most often made from wood or stone, and specifically, from a single large, carved stump or a set of two large stones. This form was very popular for large structures that required a particularly sturdy base, although it was also used for smaller structures that required protection from rats, such as beehives.
Raising a building up on staddles not only protected them from vermin, but also kept the contents of the buildings from the damp and mildew that often formed at ground level, and let air circulate through the floorboards, allowing crops to dry. These advantages were enough that staddles were quite common for centuries, although they seem to have been by far the most popular in the UK.
Staddles, particularly the stone ones, tend to outlast the structures that they support. Abandoned staddles are a common enough sight in the UK, and are often lumped under the general category of 'standing stones' -- which is accurate, but may suggest that they are more ancient than they actually are. Most staddles in the UK seem to be from the 1700s and 1800s, although some may be older. As you might expect, these staddles tend to appear in square or rectangular patterns, although they may sometimes appear to be in a 'star' pattern, if the staddles supported four corners of the building with an extra one in the middle to shore up the center of the floor. Larger buildings could often use 12-16 staddles, and one granary in Oxfordshire used 36. The number of staddles left sprinkled across the countryside has led to a number of place names with 'staddle' in them - Staddle Hill, Staddle Brook, Staddle Ranch, and even one Hobbit village named Staddle in J. R. R. Tolkien's Middle-earth.
The term 'staddle' is still used today, although by far it is most often used to refer to old staddles supporting old buildings or left standing alone in fields -- or, in some cases, replicas of these sold to decorate ones garden.
Staddle comes from the Old English staðol, meaning 'foundation' or 'support'.