The term "stackable" refers to a product or item that can be stacked on top of another, forming a tower-like structure. This means that multiple units of such products can be placed one upon the other without any support from below, creating vertical storage and organization. Stackable items are often designed with interlocking features so they fit securely together, preventing them from tipping over or collapsing under their own weight. The term is commonly used to describe furniture pieces such as chairs, tables, or shelves that can be stacked on top of each other when not in use, saving space and making storage easier.