reef

A reef is a raised area on the ocean floor that's made of rock, coral, or sand. If you are a scuba diver, head to a coral reef to check out the diverse marine life.

A barrier reef is one that surrounds an island and creates a lagoon between the reef and the beach. When this type of reef attracts diverse ocean life, it can be popular with snorkelers and scuba divers. When you're sailing, a reef is a section of the sail that you can roll up when necessary — and to reef is to roll up a reef. Both meanings share an Old Norse root, rif, "ridge under the water."

Primary Meanings of reef

1.
n
a submerged ridge of rock or coral near the surface of the water
2.
nv
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
roll up (a portion of a sail) in order to reduce its area
Full Definitions of reef
1

n a submerged ridge of rock or coral near the surface of the water

Examples:
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Bikini
an atoll in the Marshall Islands; formerly used by the United States as a site for testing nuclear weapons
Eniwetok
an atoll in the Marshall Islands; site of an amphibious assault in World War II; later used temporarily by the United States to test atomic bombs
Kwajalein
an atoll in the western Marshall Islands that was used as a Japanese air and naval base during World War II
Midway Islands
an atoll in the Hawaiian Islands some 1300 miles to the northwest of Honolulu; site of an important United States naval base
Great Barrier Reef
the largest coral reef in the world; in the Coral Sea off the northeastern coast of Australia
Types:
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coral reef
a reef consisting of coral consolidated into limestone
atoll
an island consisting of a circular coral reef surrounding a lagoon
barrier reef
a long coral reef near and parallel to the shore
Florida key, cay, key
a coral reef off the southern coast of Florida
Type of:
ridge
a long narrow natural elevation or striation
2

n 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

Type of:
slip, strip
artifact consisting of a narrow flat piece of material

v roll up (a portion of a sail) in order to reduce its area

Type of:
furl, roll up
form into a cylinder by rolling

v reduce (a sail) by taking in a reef

Type of:
reduce, shrink
reduce in size; reduce physically

v lower and bring partially inboard

reef the sailboat's mast”
Type of:
bring down, get down, let down, lower, take down
move something or somebody to a lower position

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