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(nautical) A spar attached to the outboard end of a bowsprit or flying jib boom with an additional stay to increase sail area.

A diagram of the three spars and some of the rigging that can make up a bow: A.) Bowsprit, B.) Jibboom, C.) Flying jib-boom, D.) Jibstay. E.) Fore Topgallant Stay, F.) Flying Jibstay, G.) Fore Royal Stay, H.) Topmast stays, I.) Outer Forestay, J.) Inner Forestay