(densities)
1.
Density is the extent to which something is filled or covered with people or things.
...a law which restricts the ~ of housing...
The region has a very high population ~.
N-VAR: usu with supp, oft N of n
2.
In science, the ~ of a substance or object is the relation of its mass or weight to its volume. (TECHNICAL)
N-VAR: usu with supp, oft with poss