a term in navigation. When there is a great gale of wind, they commonly roll up part of the sail below, that by this means it may become the narrower, and not draw too much wind; which contracting or taking up the sail, they call a reef, or raising the sail: so also when a topmast is sprung, as they call it, that is, when it is cracked, or almost broken in the cap, they cut off the lower piece that was near broken off, and setting the other part, part, now much shorter, in the flep again, they call it a reefed top-mast.