Sail  —n. 1 piece of material extended on rigging to catch the wind and propel a boat or ship. 2 ship's sails collectively. 3 voyage or excursion in a sailing-boat. 4 ship, esp. As discerned from its sails. 5 wind-catching apparatus of a windmill. —v. 1 travel on water by the use of sails or engine-power. 2 begin a voyage (sails at nine). 3 a navigate (a ship etc.). B travel on (a sea). 4 set (a toy boat) afloat. 5 glide or move smoothly or in a stately manner. 6 (often foll. By through) colloq. Succeed easily (sailed through the exams).  sail close to the wind 1 sail as nearly against the wind as possible. 2 come close to indecency or dishonesty. Sail into colloq. Attack physically or verbally. Under sail with sails set. [old english]