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reef
reef.
1. The means of shortening a sail to the amount appropriate to the strength of the wind, and the same word is also used as a verb to describe this action. There are various ways of reefing a sailing vessel, depending on its rig and modernity. In square-rigged ships, sails up to the topsails normally carry two rows of reef-points, enabling two reefs to be taken in. The first reef is at the head of the sail and is reefed up to its yard. The sails set above them usually have no reef-points as they are furled or sent down in a wind strong enough to require the sails to be reefed. Gaff-rigged vessels usually have three sets of reef-points in their mainsails. The mainsail is reefed by lowering it sufficiently for the reef-points to be tied under the boom, thus securing the reefed part of the sail to it. In a Bermudan rig the mainsail is reduced in size by roller reefing or slab reefing. Roller reefing is achieved either by a patent reefing gear which winds the foot of the mainsail onto the boom or the luff into the mast. See also spanish reef. 2. A group, or continuous line, of rocks lying low in, or just beneath, the sea. In 2004 Britain followed Canada, New Zealand, and Australia to create its first artificial reef with a ship when HMS Scylla was sunk at Whitsand Bay, Cornwall, a known nursery for flatfish. The new reef is being supervised by the National Marine Aquarium, Plymouth, which runs the UK Marine Fish Reporting Scheme. It is expected to attract many forms of sea life for conservationists and recreational divers to view. See also coral reefs. |
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Cite this article
"reef." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "reef." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O225-reef.html "reef." The Oxford Companion to Ships and the Sea. 2006. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O225-reef.html |
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reef
reef
1. A rigid, wave-resistant build-up constructed by carbonate organisms. Types of reef include patch reefs (small and circular in shape); pinnacle reefs (conical in form); barrier reefs (separated from the coast by a lagoon); fringing reefs (attached to a coast); and atolls (isolated reefs enclosing lagoons). Factors influencing reef growth include: (a) water temperature (optimum 25°C); (b) water depth (must be less than 10 m); (c) salinity (normal marine salinity is necessary); (d) wave action (intense wave action favours coral growth); and (e) turbidity (coral growth requires clear water and an absence of terrigenous suspended sediment). The diversity of species found in a reef will be a function of salinity and water temperature, with stressful conditions resulting in a reduction of species present. 2. In mining, certain palaeoplacer gold deposits in Australia and South Africa. |
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AILSA ALLABY and MICHAEL ALLABY. "reef." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "reef." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O13-reef.html AILSA ALLABY and MICHAEL ALLABY. "reef." A Dictionary of Earth Sciences. 1999. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-reef.html |
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reef
reef A rigid, wave-resistant structure that is built up by carbonate organisms. Types of reef include patch reefs (small and circular in shape); pinnacle reefs (conical in form); barrier reefs (separated from the coast by a lagoon); fringing reefs (attached to a coast); and atolls (isolated reefs enclosing lagoons). Factors influencing reef growth include: (a)water temperature (optimum 25°C);(b)water depth (must be less than 10 m);(c)salinity (normal marine salinity is necessary);(d)wave action (intense wave action favours coral growth); and(e)turbidity (coral growth requires clear water and an absence of terrigenous suspended sediment). The diversity of species found in a reef is related to salinity and water temperature, with stressful conditions resulting in a reduction of species present.
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Cite this article
MICHAEL ALLABY. "reef." A Dictionary of Ecology. 2004. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "reef." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O14-reef.html MICHAEL ALLABY. "reef." A Dictionary of Ecology. 2004. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-reef.html |
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reef
reef1 / rēf/ • n. a ridge of jagged rock, coral, or sand just above or below the surface of the sea. ∎ Austral. & S. Afr. a metalliferous mineral deposit, esp. one that is bedded and contains gold. reef2 Sailing • n. each of the several strips across a sail that can be taken in or rolled up to reduce the area exposed to the wind. • v. [tr.] take in one or more reefs of (a sail): reefing the mainsail in strong winds. |
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"reef." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "reef." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O999-reef.html "reef." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-reef.html |
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reef
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Cite this article
T. F. HOAD. "reef." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "reef." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O27-reef.html T. F. HOAD. "reef." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-reef.html |
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reef
reef2 ridge of rock at or near the surface of the water XVI; (in gold-mining, orig. Austral.) lode of auriferous quartz XIX. Earlier riff(e), in nautical use — MLG. ref, rif, pl. rēves, MDu. rif, ref — ON. rif (RIB) in same sense; cf. prec.
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Cite this article
T. F. HOAD. "reef." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "reef." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O27-reef1.html T. F. HOAD. "reef." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-reef1.html |
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reef
reef n. each of the several strips across a sail that can be taken in or rolled up to reduce the area exposed to the wind.
v. 1. take in one or more reefs of (a sail): reefing the mainsail in strong winds. 2. shorten (a topmast or a bowsprit). |
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"reef." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "reef." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O63-reef.html "reef." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-reef.html |
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reef
reef Rocky outcrop lying in shallow water, especially one built up by corals or other organisms.
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"reef." World Encyclopedia. 2005. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "reef." World Encyclopedia. 2005. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O142-reef.html "reef." World Encyclopedia. 2005. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-reef.html |
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reef
reef see coral reef . |
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"reef." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "reef." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1E1-X-reef.html "reef." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-reef.html |
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reef
reef •aperitif, beef, belief, brief, chief, enfeoff, fief, grief, interleaf, leaf, Leif, lief, Mazar-e-Sharif, misbelief, motif, naif, O'Keeffe, reef, seif, Sharif, sheaf, shereef, sportif, Tenerife, thief
•tea leaf • fig leaf • bas-relief • flyleaf
•drop-leaf • broadleaf • cloverleaf
•massif • leitmotif
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"reef." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "reef." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O233-reef.html "reef." Oxford Dictionary of Rhymes. 2007. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-reef.html |
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