Papal States. Large Silver Piastra minted in 1689.

Papal States Piastra Large Silver coin
Papal States, Sede Vacante. Large Silver Piastra coin
Papal States, Sede Vacante. Large Silver Piastra minted in 1689.

Obverse: Umbrella and crossed keys above arms of Cardinal Paluzzo Altieri, who was acting as office holder during the Sede Vacante.
Legend: SEDE · VACAN - TE · MDCLXXXIX

Reverse: Dove (the Holy Spirit), surrounded by light. Papal legate´s arms splitting legend (RO-MA) below.
Legend: EMITTE · SPIRITVM ·TVVM
Translated: "[God] send your spirit"

Mint Place: Rome (Papal State)
Mint date: 1689 (MDCLXXXIX)
Denomination: Scudo of 80 Bolognini (Piastra)
Reference: Davenport 4098, Muntoni 3, Berban 2159, KM-497.
Weight: 31.89 gm
Diameter: 44 mm

Sede vacante is an expression, used in the Canon Law of the Roman Catholic Church, that refers to the vacancy of the episcopal see (the official seat of a bishop) of a particular church. It is Latin for "the seat being vacant" (the ablative absolute to sedes vacans "vacant seat"), that is, the cathedra of the particular church.

Holy Spirit is a term introduced in the Hebrew Bible, though understood differently in the main Abrahamic religions.