A graveyard is an area where the dead are buried. When you walk through a historic graveyard, you'll see many beautiful old headstones and tombs.
Other names for a graveyard are "cemetery" and "burial ground." It's slightly more common to use graveyard, a word that dates from about 1683, for the burial site near a church. If you work at a graveyard, you might care for the grave markers and plants. If, on the other hand, you work a graveyard shift, that simply means you work late at night.