(covers information from several alternate timelines)
A graveyard, cemetery, or burial site was a place where, after death, a person's body was traditionally buried in a grave. Such locations were typically accompanied by gravestones. Gravediggers usually worked here. (ENT: "A Night in Sickbay"; TNG: "A Fistful of Datas", "Sub Rosa")
In 2152, Captain Jonathan Archer of the starship Enterprise NX-01 experienced a dream in which he was burying his dog Porthos in a cemetery exclusive for pets. (ENT: "A Night in Sickbay")
Rura Penthe was known throughout the galaxy as "the alien's graveyard." (Star Trek VI: The Undiscovered Country)
When a Tarellian ship approached Haven in 2364, Valeda Innis told Commander Riker this ship could turn their "lovely world" into a graveyard due to the Tarellian plague. (TNG: "Haven")
In 2365, Geordi La Forge referred to the surface of Surata IV as a graveyard after Data discovered fossilized animal remains. (TNG: "Shades of Gray")
In 2370, Doctor Beverly Crusher, along with Captain Jean-Luc Picard and Counselor Deanna Troi visited the cemetery at the Caldos colony on Caldos for the funeral of Felisa Howard, Crusher's grandmother. (TNG: "Sub Rosa")
In an alternate 2371, Commander Chakotay compared walking around on a planet in the Delta Quadrant devastated by polaric ion energy akin to being in a graveyard. (VOY: "Time and Again")
In 2371, the USS Voyager unsuccessfully attempted to evade the Vidiians by entering a part of space surrounded by numerous subspace vacuoles. Captain Kathryn Janeway compared it to sneaking around a graveyard at night. (VOY: "Fury")
Also in that year, the crew of Voyager discovered the burial site of the Vhnori on the asteroids surrounding a class D planet. (VOY: "Emanations")
In 2374, Dukat told Captain Benjamin Sisko that he regretted not killing all Bajorans during the Occupation of Bajor and turning Bajor into a graveyard. (DS9: "Waltz")