Ghost (slang)

From Memory Alpha, the free Star Trek reference

A "ghost" is a 21st century slang term for a person who lives in a Sanctuary District but has not integrated well into the environment. They are considered dangerous for their violence and hostility towards other residents.

Biddle Coleridge was the leader of the "ghosts" in Sanctuary District A in 2024. (DS9: "Past Tense, Part I", "Past Tense, Part II")