reef1
n.
- a ridge of jagged rock, coral, or sand just above or below the surface of the sea.
- a vein of gold or other ore.
Etymology
C16 (earlier as riff): from Mid. Low Ger. and MDu. rif, ref, from ON rif, lit. ‘rib’; cf. reef2.
reef2
n.
each of several strips across a sail which can be taken in or rolled up to reduce the area exposed to the wind.
v.
take in one or more reefs of (a sail).
▸shorten (a topmast or a bowsprit).
Etymology
ME: from MDu. reef, rif, from ON rif, lit. ‘rib’; cf. reef1.
