The definition of a ghost is a faint hint of something, or the spirit of a dead person come back to Earth to haunt the living.(noun)
See ghost in Webster's New World College Dictionary
Origin: altered (prob. after Fl gheest) < ME goste < OE gast, soul, spirit, demon, akin to Ger geist < IE base *gheizd-, to be excited, frightened > Sans hēḋ-, to be angry
See ghost in American Heritage Dictionary 4
Origin: Middle English gost
Origin: , from Old English gāst, breath, spirit.
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