6,500 years ago, we think that some people were using the word gheis to describe fear and amazement. That origin haunts us today. After gheis, etymologists trace the word to the reconstructed Proto-Germanic term gaistaz, which meant "ghost or spirit", since one shows fear and amazement at seeing a spectral apparition. The Proto-Germanic word then gave way to many other Germanic words (more on this later), including the English word gast. Gast then split and gave us both ghast (of ghastly) and ghost (of ghostly). Now, you may have noticed that a silent h got inserted into both of those words. An amateur etymologist like myself would think that it's an influence of Latin folk etymology, but the change is much simpler than that. It can be attributed to a ghost in the machine: a faulty printer. What a ghastly change!
Adam Aleksic has been described as the internet's sixth most famous etymologist. He loves writing about himself in the third person, he's a freshman at Harvard University, and he has disturbing interests in linguistics, vexillology, geography, board games, limericks, and law.
The Etymology Nerd