lower class
People who already earned the most gained more in wages than those workers in the middle and lower classes, according to the report.
The upper classes don't want the lower classes to succeed.
Because of their disgusting treatment of the lower classes, they carried the country to catastrophe.
In short order, the upper echelons of patrons and priests in the society lived off the work of the lower classes.

SMART Vocabulary: related words and phrases

Class & class-consciousness in general
anti-bourgeois
anti-snob
arriviste
bougie
gentrification
gentrify
go/come down in the worldidiom
go/come up in the worldidiom
petty bourgeois
pleb
plebby
plebeian
the bottom of the heapidiom
the gentry
the petite bourgeoisie
the upper crust
underclass
ungenteel
ungentrified
upper class