Ghost of Honor

It is moderately common for conventions to deliberately list a deceased person as a guest of honor with the intention of drawing special attention to that person's contributions to the field.

This is slightly controversial — a few feel that it is always tacky — but the majority opinion seems to be that if done with dignity, it's a Good Thing. Unfortunately, the most common title used is "Ghost of Honor," and many people who approve of having a posthumous guest object to the punning title. As you might expect, the temptation to pun "ghost" for "guest" is nearly irresistible, so we also see Honored Ghost. Less punny terms like "Memorial Guest", "Historical Guest", and ''Posthumous GoH" are also used and produce fewer objections.

This title is never used for a Guest of Honor who died after being invited. The normal practice in a case like that is to continue to list the person as a GoH, but to note that they are deceased. Sometimes an additional GoH is invited and added to the list; sometimes not. But it's hyper-tacky to delist a GoH for any reason other than their own choice, and most particularly to do so because they died.