What is (a) The longitudinal upward curvature of the deck, gunwale, and lines of a vessel, as when viewed from the side. (b) The position of a vessel riding at single anchor and swinging clear of it called?

sheer — (Naut.) (a) The longitudinal upward curvature of the deck, gunwale, and lines of a vessel, as when viewed from the side. (b) The position of a vessel riding at single anchor and swinging clear of it. (Webster's 1913.)

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