The sort of fear that makes people insist they be buried in a coffin with a bell to the surface just in case they were really just in some sort of suspended animation and everyone happened to mess up the diagnosis of death (including the embalmer, I gather). But I should not mock -- as Wikipedia notes, "Before the advent of modern medicine, the fear was not entirely irrational. Throughout history, there have been numerous cases of people being buried alive by accident." The word was coined from Greek roots, taphḗ, grave + ye standard -phobia.
As the immigration official piled still more forms between us, the stacks threatened to topple over and bury me, and my taphephobia triggered a panic attack that I only barely controlled -- but left him even more suspicious of my intentions.