The line of the upper deck when viewed from the side. Normal sheer curves up towards the bow and stern. Reverse sheer curves down towards the bow and stern. Compound sheer, curving up at the front of the boat and down at the stern, and straight sheer are uncommon. Or -The fore-and-aft vertical curve of a vessel's deck or rail of bulwarks. To sheer is to put the rudder over when a vessel is at anchor, so as to cause her to move laterally and ride clear of her anchor. A vessel is said to break her sheer when she departs from the sheer that has been given her. Also To move through the water after the means of propulsion is withdrawn.