second-class citizen
n.
A person considered inferior in status or rights in comparison with some others: “He believes women... are second-class citizens under the Constitution” (Edward M. Kennedy).

[TahlilGaran] American Dictionary ▲

a second-class citizen
someone who is treated as if they are less important than other people in society.
Although she was married to an Australian, Louise couldn't get a work visa and it made her feel like a second-class citizen.

[TahlilGaran] English Idioms Dictionary ▲