noun (1)
\ˈrēf \

Definition of reef 

(Entry 1 of 3)

1 : a part of a sail taken in or let out in regulating size

2 : reduction in sail area by reefing


reefed; reefing; reefs

Definition of reef (Entry 2 of 3)

transitive verb

1 : to reduce the area of (a sail) by rolling or folding a portion

2 : to lower or bring inboard (a spar) wholly or partially

intransitive verb

: to reduce a sail by taking in a reef


noun (2)

Definition of reef (Entry 3 of 3)

1a : a chain of rocks or coral or a ridge of sand at or near the surface of water — compare atoll, barrier reef

b : a hazardous obstruction

2 : lode, vein

Other Words from reef


reefable \ˈrē-​fə-​bəl \ adjective

Noun (2)

reefy \ˈrē-​fē \ adjective

First Known Use of reef

Noun (1)

14th century, in the meaning defined at sense 1


1670, in the meaning defined at transitive sense 1

Noun (2)

1584, in the meaning defined at sense 1a

History and Etymology for reef

Noun (1)

Middle English riff, from Old Norse rif; probably akin to Old Norse rīfa to rend — more at rive

Noun (2)

Dutch rif, from Middle Dutch, from Old Norse, literally rib; akin to Old English ribb rib — more at rib

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Time Traveler for reef

The first known use of reef was in the 14th century

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\ˈrēf \

Kids Definition of reef

: a chain of rocks or coral or a ridge of sand at or near the surface of water

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More from Merriam-Webster on reef

Rhyming Dictionary: Words that rhyme with reef

Spanish Central: Translation of reef

Nglish: Translation of reef for Spanish Speakers

Britannica English: Translation of reef for Arabic Speakers Encyclopedia article about reef

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having a pattern of small flowers

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