French cénotaphe, from Latin cenotaphium, from Greek kenotaphion, from kenos empty + taphos tomb
First Known Use: 1578
From the Concise Encyclopedia:
(Greek: “empty tomb”) Monument, sometimes in the form of a tomb, to a person buried elsewhere. Ancient Greek writings tell of many cenotaphs, none of which survives. Existing cenotaphs of this type are found in churches (e.g., in Santa Croce, Florence, where there are memorials to Dante, Niccolo Machiavelli, and Galileo). The term is now applied to national war memorials.
Recently seen in this article from Mental Floss: http://mentalfloss.com/article/52301/grave-sightings-joseph-schlitz-brewing-magnate