A subaltern is someone with a low ranking in a social, political, or other hierarchy. It can also mean someone who has been marginalized or oppressed.
From the Latin roots sub- ("below"), and alternus ("all others"), subaltern is used to describe someone of a low rank (as in the military) or class (as in a caste system). Subalterns occupy entry-level jobs or occupy a lower rung of the "corporate ladder." But the term is also used to describe someone who has no political or economic power, such as a poor person living under a dictatorship.