reef /ɹiːf/verb 4noun 6adjective 1forms 7 verb4 •To take in part of a sail in order to adapt the size of the sail to the force of the wind."When the day arrived that the boy was to be skipper, the weather was calm and fine, but he called all men to reef sails, so the ship had scarcely any sail on her." — 1886 •To move the floats of a paddle wheel toward its center so that they will not dip so deeply.Reef the paddles. •(Australia) To pull or yank strongly, especially in relation to horse riding.He reefed on the handbrake and sat smoking his cigarette, gazing out through the windscreen at the driveway. — 2002 •(slang) To manipulate the lining of a person's pocket in order to steal the contents unnoticed. noun6 •A chain or range of rocks, sand, or coral lying at or near the surface of the water. •A portion of a sail rolled and tied down to lessen the area exposed in a high wind. •A reef knot. •(Australia, South-Africa) A large vein of auriferous quartz; hence, any body of rock yielding valuable ore. •The itch; any eruptive skin disorder. •Dandruff. adjective1 •Scabby; scurvy. formsreefed · reefing · reefs · more reef · reefer · most reef · reefest