The word for today is…
apparition (noun) – 1. A ghostly figure; a spectre.
2. A sudden or unusual sight.
3. The act of appearing; appearance.
Source : The Free Dictionary
Etymology : Circa 1500, “unclosing” (of Heaven), from Anglo-French aparicion, Old French apparition, aparoison (15th century), used in reference to the Epiphany (revealing of Christ child to the Wise Men), from Late Latin apparitionem (nominative apparitio) “an appearance,” also “attendants,” in classical Latin “service, servants,” noun of action from past participle stem of apparere “appear”. Meaning “ghost” first recorded circa 1600; the shade of sense differentiation between appearance and apparition is that the latter tends to be unexpected or startling.