reef

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A strip or ridge of rocks, sand, or coral that rises to or near the surface of a body of water.
• noun A vein of ore.
• noun A portion of a sail rolled and tied down to lessen the area exposed to the wind.
• transitive verb To reduce the size of (a sail) by tucking in a part and tying it to or rolling it around a yard.
• transitive verb To shorten (a topmast or bowsprit) by taking part of it in.

from The Century Dictionary.

• noun Nautical, a part of a sail rolled or folded up, in order to diminish the extent of canvas exposed to the wind.
• In Australian mining, to work at a reef.
• Scabby; scurvy.
• noun The itch; also, any eruptive disorder.
• noun Dandruff.
• Nautical, to take a reef or reefs in; reduce the size of (a sail) by rolling or folding up a part and securing it by tying reef-points about it.
• To gather up stuff of any kind in away similar to that described in def. 1. Compare reefing.
• See the quotation.
• noun In the Tyrolese Alps, and especially in the region of the dolomites, “massive un-stratified limestones and dolomites rising amid strikingly contrasted sediments.”
• noun A low, narrow ridge of rocks, rising ordinarily but a few feet above the water.
• noun Any extensive elevation of the bottom of the sea; a shoal; abank: so called by fishermen.
• noun In Australia, the same as lode, vein, or ledge of the Cordilleran miner: as, a quartz-reef (that is, a quartz-vein).
• noun A kind of commercial sponge which grows on reefs.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb (Naut.) To reduce the extent of (as a sail) by rolling or folding a certain portion of it and making it fast to the yard or spar.
• transitive verb to move the floats of a paddle wheel toward its center so that they will not dip so deeply.
• noun (Naut.) That part of a sail which is taken in or let out by means of the reef points, in order to adapt the size of the sail to the force of the wind.
• noun the last reef that can be put in.
• noun See Reef-band in the Vocabulary.
• noun the knot which is used in tying reef pointss. See Illust. under Knot.
• noun a small rope formerly used to reef the courses by being passed spirally round the yard and through the holes of the reef.
• noun pieces of small rope passing through the eyelet holes of a reef-band, and used reefing the sail.
• noun a tackle by which the reef cringles, or rings, of a sail are hauled up to the yard for reefing.
• noun to reduce the size of (a sail) by folding or rolling up a reef, and lashing it to the spar.
• noun A chain or range of rocks lying at or near the surface of the water. See Coral reefs, under coral.
• noun (Mining.) A large vein of auriferous quartz; -- so called in Australia. Hence, any body of rock yielding valuable ore.
• noun (Zoöl.) any stony coral which contributes material to the formation of coral reefs.
• noun (Zoöl.) any heron of the genus Demigretta.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Scabby; scurvy.
• noun The itch; any eruptive skin disorder.
• noun Dandruff.
• noun A chain or range of rocks, sand, or coral lying at or near the surface of the water.
• noun Australia, South Africa A large vein of auriferous quartz; hence, any body of rock yielding valuable ore.
• noun nautical A portion of a sail rolled and tied down to lessen the area exposed in a high wind.
• noun A reef knot.
• verb nautical To take in part of a sail in order to adapt the size of the sail to the force of the wind.
• verb Australia To pull or yank strongly.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• verb reduce (a sail) by taking in a reef
• noun one of several strips across a sail that can be taken in or rolled up to lessen the area of the sail that is exposed to the wind
• noun a submerged ridge of rock or coral near the surface of the water
• noun a rocky region in the southern Transvaal in northeastern South Africa; contains rich gold deposits and coal and manganese
• verb roll up (a portion of a sail) in order to reduce its area
• verb lower and bring partially inboard