From WordNet (r) 3.0 (2006) [wn]:
reef
n 1: a submerged ridge of rock or coral near the surface of the
water
2: a rocky region in the southern Transvaal in northeastern
South Africa; contains rich gold deposits and coal and
manganese [syn: Witwatersrand, Rand, Reef]
3: 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
v 1: lower and bring partially inboard; "reef the sailboat's
mast"
2: roll up (a portion of a sail) in order to reduce its area
3: reduce (a sail) by taking in a reef
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Reef \Reef\ (r[=e]f), n. [Akin to D. rif, G. riff, Icel. rif,
Dan. rev; cf. Icel. rifa rift, rent, fissure, rifa to rive,
bear. Cf. Rift, Rive.]
1. A chain or range of rocks lying at or near the surface of
the water. See Coral reefs, under Coral.
[1913 Webster]
2. (Mining.) A large vein of auriferous quartz; -- so called
in Australia. Hence, any body of rock yielding valuable
ore.
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Reef builder (Zool.), any stony coral which contributes
material to the formation of coral reefs.
Reef heron (Zool.), any heron of the genus Demigretta;
as, the blue reef heron (Demigretta jugularis) of
Australia.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Reef \Reef\, n. [Akin to D. reef, G. reff, Sw. ref; cf. Icel.
rif reef, rifa to basten together. Cf. Reeve, v. t.,
River.] (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.
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Note: From the head to the first reef-band, in square sails,
is termed the first reef; from this to the next is the
second reef; and so on. In fore-and-aft sails, which
reef on the foot, the first reef is the lowest part.
--Totten.
[1913 Webster]
Close reef, the last reef that can be put in.
Reef band. See Reef-band in the Vocabulary.
Reef knot, the knot which is used in tying reef pointss.
See Illust. under Knot.
Reef line, a small rope formerly used to reef the courses
by being passed spirally round the yard and through the
holes of the reef. --Totten.
Reef points, pieces of small rope passing through the
eyelet holes of a reef-band, and used reefing the sail.
Reef tackle, a tackle by which the reef cringles, or rings,
of a sail are hauled up to the yard for reefing. --Totten.
To take a reef in, to reduce the size of (a sail) by
folding or rolling up a reef, and lashing it to the spar.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Reef \Reef\, v. t. [imp. & p. p. Reefed (r[=e]ft); p. pr. &
vb. n. Reefing.] (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.
--Totten.
[1913 Webster]
To reef the paddles, to move the floats of a paddle wheel
toward its center so that they will not dip so deeply.
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