- a ridge of rocks or sand, often of coral debris, at or near the surface of the water.
- a lode or vein.
- a part of a sail that is rolled and tied down to reduce the area exposed to the wind.
- to shorten (sail) by tying in one or more reefs.
- to reduce the length of (a topmast, a bowsprit, etc.), as by lowering, sliding inboard, or the like.
- to pull (old oakum) out of seams, as with a rave hook (often followed by out).
- a ridge of rock, sand, coral, etc, the top of which lies close to the surface of the sea
- a ridge- or mound-like structure built by sedentary calcareous organisms (esp corals) and consisting mainly of their remains
- a vein of ore, esp one of gold-bearing quartz
- the part gathered in when sail area is reduced, as in a high wind
- to reduce the area of (sail) by taking in a reef
- to shorten or bring inboard (a spar)
- another name for the Great Barrier Reef
- another name for the Witwatersrand