On the escutcheon’s upper half, on the dexter (armsbearer’s right, viewer’s left) side, are the arms formerly borne by the Prince-Bishopric (Hochstift) of Würzburg, referring to the community’s former allegiance to that state. On the sinister (armsbearer’s left, viewer’s right) side, the two staves refer to the special tithe court whose seat Mittelsinn once was. They also symbolize the Hessian-Bavarian condominium that existed here from the early 19th century until 1866. From the 15th century, the lordship and court rights over Mittelsinn were held by several lords, leading to the creation of the "Vierherrschaft", or “Four-Lordship”. Prime among these lords were the Lords of Thüngen and the Lords of Hutten, to whom the tinctures Or and gules (gold and red) refer, as both noble families’ arms showed these tinctures. The charges in the escutcheon's lower half, a waterwheel and a wavy pale (vertical stripe) symbolize the River Sinn and its mills. The tincture vert (green) stands for the community's rural character and for its location between the Rhön and the Spessart.