Definition of "succinctorium" []

• A vestment worn on solemn occasions by the Pope, similar in shape to a maniple, and hanging on his left side from a cincture or girdle (also called succinctorium or subcingulum) answering to the lower of the two girdles formerly worn by bishops with a similar pendent ornament, sometimes on both sides. (noun)
• Same as subcingulum. (noun)

The Century Dictionary (Public Domain)

• "New pontifical vestments were the gloves, the succinctorium, and the mitre, to which were added among the German bishops the rational, an imitation of the pallium."