A tuple is a fixed fixed-length list containing elements that need not have the same type. It can be, and often is, used as a key-value pair. A row (sometimes called a record) is the set of fields within a table that are relevant to a specific entity.
The stem wall on a concrete foundation is essentially the supporting wall that joins the foundation of a building to the vertical walls of the structure that is constructed atop the foundation.
Cell wall: The cell wall is a rigid layer that surrounds the plant cells. Plant cell walls are primarily made up of cellulose. It is located outside the cell membrane whose main function is to provide rigidity, strength, protection against mechanical stress and infection.