Yes, it's a concept used e.g. in hash tables that use open addressing [0], where you can't delete value X because the final address of value Y may depend on whether X was present when it was being inserted. So instead of deleting X and leaving behind an empty address we change X to a tombstone that stays there forever and says "something was here and if you're looking for Y, Z or anything else, keep on looking".

[0] https://en.wikipedia.org/wiki/Hash_table#Open_addressing

Thank you