reef

1
[ reef ]
/ rif /

noun

a ridge of rocks or sand, often of coral debris, at or near the surface of the water.
Mining. a lode or vein.

Origin of reef

1
1575–85; earlier riff(e) < Dutch rif

Definition for reef (2 of 2)

reef

2
[ reef ]
/ rif /
Nautical

noun

a part of a sail that is rolled and tied down to reduce the area exposed to the wind.

verb (used with object)

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).

Origin of reef

2
1350–1400; Middle English refe (noun) < Dutch reef

Related forms

un·reefed, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for reef

British Dictionary definitions for reef (1 of 3)

reef

1
/ (riːf) /

noun

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

Word Origin for reef

C16: from Middle Dutch ref, from Old Norse rif rib 1, reef ²

British Dictionary definitions for reef (2 of 3)

reef

2
/ (riːf) nautical /

noun

the part gathered in when sail area is reduced, as in a high wind

verb

to reduce the area of (sail) by taking in a reef
(tr) to shorten or bring inboard (a spar)

Word Origin for reef

C14: from Middle Dutch rif; related to Old Norse rif reef, rib 1, German reffen to reef; see reef 1

British Dictionary definitions for reef (3 of 3)

Reef

/ (riːf) /

noun the Reef

another name for the Great Barrier Reef
another name for the Witwatersrand

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for reef

reef

[ rēf ]

A strip or ridge of rocks, sand, or coral that rises to or near the surface of a body of water. See more at coral reef.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.