The Cross Moline is a difference, or mark of cadency in English heraldry. It is so called because its shape resembles a millrind (the iron clamp of the upper millstone). It is borne both inverted and rebated, and sometimes saltirewise or in saltire. When used as a mark of cadency it represents the eighth son.

This article incorporates text from the public domain Pimbley's Dictionary of Heraldry

Heraldry