E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
The last seven days of Passion Week or the Great Week. It begins on Palm Sunday, and ends with Holy Saturday (q.v.). The fourth day is called Spy Wednesday; the fifth is Maundy Thursday; the sixth is Good Friday; and the last Holy Saturday or the Great Sabbath.
Holy Week has been called Hebdomada Muta (Silent Week); Hebdomada Passionis; Hebdomada Inofficiosa (Vacant Week); Hebdomada Penitentialis: Hebdomada Indulgenti; Hebdomada Luctuosa; Hebdomada Nigra; and Hebdomada Ultima.