reef

Short definition from Wiktionary

Noun

1. 1
   A chain or range of rocks, sand, or coral lying at or near the surface of the water.
2. 2
   A large vein of auriferous quartz; hence, any body of rock yielding valuable ore.
3. 3
   A portion of a sail rolled and tied down to lessen the area exposed in a high wind.
4. 4
   A reef knot.
5. 5
   The itch; any eruptive skin disorder.
6. 6
   Dandruff.

Verb

1. 1
   To take in part of a sail in order to adapt the size of the sail to the force of the wind.
2. 2
   To pull or yank strongly, especially in relation to horse riding.
3. 3
   To move the floats of a paddle wheel toward its center so that they will not dip so deeply.
4. 4
   To manipulate the lining of a person's pocket in order to steal the contents unnoticed.

Adjective

1. 1
   Scabby; scurvy.

Proper noun

1. 1
   A surname from German.