Answer:
\(\boxed{\mathrm{many \ people \ living \ in \ a \ small \ area}}\)
Explanation:
Population density is a measurement of population per land area.
\(\displaystyle \sf population \ density =\frac{population}{land \ area}\)
The population density of a place tells us whether the place occupied by the population is densely or sparsely populated.
An area with a high population density has many people living in a small area.