Poverty was the state of being poor or a pauper, or having little to no money or possessions and lacking wealth.
Poverty was prevalent during the Great Depression, causing people to turn to places like the 21st Street Mission for shelter. (TOS: "The City on the Edge of Forever")
According to Natasha Yar, poverty and violence drove many of the people on her home planet to substance abuse. (TNG: "Symbiosis")
Deanna Troi told Mark Twain that poverty was eliminated on Earth a long time ago, taking with it hopelessness, despair, and cruelty, to which Twain replied that maybe such a world was worth giving up cigars for after all. Years later, when trying to convince Zefram Cochrane to make his famous first warp speed flight in 2063, Troi told him that poverty would be gone within the next fifty years. (TNG: "Time's Arrow, Part II"; Star Trek: First Contact)
By 2370 this was true for Earth, unlike the planets in the Demilitarized zone. Benjamin Sisko stated this fact to Kira Nerys when attempting to explain why the Maquis were rebelling. (DS9: "The Maquis, Part II")
The Humans on the Briori colony planet likewise managed to eliminate poverty. (VOY: "The 37's")
When welcoming Neelix (disguised as the Grand Proxy) to their Divine Vault in Takar, Arridor claimed that theirs was a "poverty-stricken little world". (VOY: "False Profits")
On Vashti, a planet to which Starfleet had relocated Romulan refugees, poverty originally did not exist, but it had appeared by 2399. (PIC: "Absolute Candor")