Any imaginary place where spiritual beings (demons or fairies or angels or the like) abide(noun)
WordNet. Princeton University. 2010.
Use "spirit world" in a sentence
"The spirit world was presumed to be nonphysical because it could not be readily perceived by our conventional physical senses of seeing, hearing, tasting, smelling, and touching."
"CHANNELING: A medium is a person who can tap into the spirit world and receive messages."
"The Hopi say the hisatsinom were fulfilling a prophecy—to wander for hundreds of years before returning to the spirit world again."