Figuring out how to say "ghost" in Japanese should be pretty easy. Then you look it up on Jisho.org, and 91 different words pop up. Yikes!
Rather than attempt to give my own severely lacking explanation on how to say ghost in Japanese, I'm going to defer to a fantastic post by Japanese ghost and folklore expert Zack Davisson, founder of one of my favorite Japanese-related blogs in the world: Hyakumonogatari Kaidanka.
How Do You Say Ghost in Japanese?
Just as in English, there are several words [in Japanese] meaning “ghost,” but each with a different usage and feel.
All(most) all Japanese words for ghost use some variation on the kanji 霊.
霊 can be read as either –rei or –ryō (or tama, or mitama, or –ki ). Whatever the pronunciation, 霊 always retains the rough meaning of spirit.
Here is a list and definition of all the Japanese words for ghost that I know.
幽霊 – yūrei – 幽 (dim) +霊 (spirit) – Probably the most common Japanese word for ghost.
For the entire list of Japanese words for ghost, please see Zack's full article on this page.
Finally find out the difference between 幽霊 and 化け物. Find out which Japanese word for ghost is used when describing Hamlet's father.
Then go explore the rest of his site. Find out which mysterious animal will come and eat your dreams. Or maybe learn what those weird bobble-head creatures are in the movie Princess Mononoke. Most importantly, find out all about the ever-intriguing, um, Eyeball Butt.
Many thanks to Zack Davisson for allowing us to reprint a portion of his article, "How Do You Say Ghost in Japanese?"
Good luck with your studies, everyone.
p.s. To learn all the Japanese words, go to NativShark.