Ghost

Why does the word ghost contain a silent h? "The h is not sounded, as it was only added under the impression that such a mysterious word needed the mysterious breathing of an h to produce its effect. The same applied to the spelling aghast, originally written agast; but it does not apply to ghoul, a grave robber, in which the gh is derived from an Arabic guttural" (Paul D. Hugon, The Modern Word Finer, 1927, p. 142).

Pictured is a silent H from Calico Ghost Town, California (thanks Leo Reynolds).

Nomme Domme

In the folklore of West Cornwall, England, "Nomme Domme" was a name that spirit-quellers used to address and obtain power over ghosts. The name is undoubtedly a corruption of the Latin In Nomine Domini ("In the Name of the Lord"). The name was considered "a magical word, very likely the spirit's name among spirits, for old folks held that they acquire new ones quite different from what they bore when in mortal bodies" (William Bottrell, Stories and Folk-Lore of West Cornwall, 1880).