A patron was one bestowing patronage, the sponsoring of artists or good works. This tradition existed on Earth and Kelis' homeworld.
The Sisters of Hope Infirmary, which operated in San Francisco on Earth in 1893, had a board of patrons. (TNG: "Time's Arrow, Part II")
In 2374, a Leonardo da Vinci hologram was stolen from USS Voyager and activated on a strange world. Unable to comprehend the situation, Leonardo tried to comprehend his surroundings in 16th century terms and considered his captor to be a new patron. (VOY: "Concerning Flight")
On Kelis' homeworld, autarchs might sponsor poets to produce plays for their enjoyment. (VOY: "Muse")