Take a reef is a nautical expression meaning to reduce the area of a sail, either by folding or rolling it up. Other nautical synonyms for take a reef include reef the sail, shorten sail, reduce sail, furl the sails, pull in the sails, or make the sails smaller. These terms are used primarily in sailing, when the wind is strong, and the sail needs to be reduced to prevent the boat from being overpowered or capsized. In a broader context, synonyms for taking a reef can be used to signify reducing, limiting, or moderating something to prevent it from becoming too big, excessive, or overwhelming.