ghost

The noun is derived from Middle English gost, from Old English gāst, gǣst (“breath, spirit, soul, ghost”) (compare modern English Holy Ghost), from Proto-West Germanic *gaist, from Proto-Germanic *gaistaz, from Proto-Indo-European *ǵʰéysdos, from *ǵʰéysd- (“anger, agitation”).

The h in the spelling appears in the Prologue to William Caxton’s Royal Book, printed in 1484, in a reference to the “Holy Ghoost”. It was likely influenced by Middle Dutch gheest, a common variant of geest. Both Caxton and his assistant Wynkyn de Worde had connections to the Low Countries. Doublet of geist.

The adjective and verb are derived from the noun. The verb gained prominence in the 2010s.