👉 In mathematics, a dimensionful quantity is an entity that can be used as a measure of size or spatial extent. For example, in physics and engineering, a volume or surface area are commonly defined as dimensions. In algebra and analysis, a dimensionful quantity is one whose value depends only on the absolute magnitude of its numerical values. In general, a dimensionful quantity is a number that can be used to measure quantities with some kind of specific meaning in terms of space or space-time. For example
