The noun עם (people) in its broad meaning includes all individuals of the people, and in its precise meaning does not include priests and Levites at all. For instance, when it saysעם הקהל (people of the assembly), the noun עם comes to modify the noun קהל, which includes everyone – with this עם, it comes in its precise meaning, and priests and Levites are excluded. But when it comes alone, עם sometimes comes in its broad meaning and everyone is included.

And when it wants to distinguish between the dignitaries and the multitudes, it calls the multitudes with the name עם הארץ.