Linear density is the amount of mass for every unit of length. This is an attribute commonly associated with one-dimensional objects, although it can also be used in referring to the density of a three-dimensional quantity for a specific dimension.
Long, narrow objects, such as thin rods and strings, use linear density as one of their specifications. The term is also used in drawing or printing to refer to how densely or heavily a line is drawn.
Linear density branches out to other measurements such as linear mass density and linear charge density. Some of the units used for linear density are ounce per foot, pound per foot, ounce per inch, pound per inch and kilogram per meter.