sail

1. (noun) A piece of fabric attached to a boat and arranged such that it causes the wind to drive the boat along. The sail may be attached to the boat via a combination of mast, spars and ropes. 2. (noun) (nautical,uncountable) The concept of a sail or sails, as if a substance. 3. (noun) The power harnessed by a sail or sails, or the use of this power for travel or transport. 4. (noun) A trip in a boat, especially a sailboat. 5. (noun) (plural "sail") A sailing vessel; a vessel of any kind; a craft. 6. (noun) The blade of a windmill. 7. (noun) A tower-like structure found on the dorsal (topside) surface of submarines. 8. (noun) The floating organ of siphonophores, such as the Portuguese man-of-war. 9. (noun) A sailfish. 10. (noun) An outward projection of the spine, occurring in certain dinosaurs and synapsids 11. (noun) Anything resembling a sail, such as a wing.