Other forms: reefs, reeves, reefing
A reef is a ridge of coral or rock lying just below the surface of the sea. A coral reef, the reef protects the bay, run aground on a reef.
Coral reefs are built by tiny animals over thousands of years and support about a quarter of all marine species on a fraction of a per cent of the ocean floor. The Great Barrier Reef is the largest structure made by living things on earth. For sailors a reef is a hazard, which is the older sense. There is also a nautical verb: to reef a sail is to reduce its area in strong wind.
1nounreefA ridge of coral or rock just below the sea surface.
“The reef takes the force out of every wave.”
synonyms: coral reef
2verbreduceTo reduce the area of a sail.
“They reefed the mainsail before the squall arrived.”
reef is an underwater ridge.
Also accepted in games: coral reef
Old Norse rif meant a rib, and the ridge of rock was named for its shape. The sail sense comes from the same word by a different route: the band of canvas rolled down is also a rib along the sail.
Proto-Indo-European
*h₁rebʰ- — arch, ceiling, cover
Proto-Germanic
*ribją — rib, reef
Old Norse
rif — rib, reef
Middle English
rif
English, today
reef
Built from
From earlier riff, from Middle English rif, from Old Norse rif (“rib, reef”), from Proto-Germanic ribją (“rib, reef”), from Proto-Indo-European h₁rebʰ- (“arch, ceiling, cover”). Dutch rif (“reef”), Low German riff, reff (“reef”), German Riff (“reef, ledge”) are also borrowed from Old Norse. a doublet of rib.
Etymology from Wiktionary, CC BY-SA
Practised in Nature & Weather, Sea & Sailing