to throw, as a lance or dart; to hurl; to let fly.-to strike with, or as with, a lance; to pierce.-to cause to move or slide from the land into the water; to set afloat; as, to launch a ship.-to send out; to start (one) on a career; to set going; to give a start to (something); to put in operation; as, to launch a son in the world; to launch a business project or enterprise.-to move with force and swiftness like a sliding from the stocks into the water; to plunge; to make a beginning; as, to launch into the current of a stream; to launch into an argument or discussion; to launch into lavish expenditures; -- often with out.-the act of launching.-the movement of a vessel from land into the water; especially, the sliding on ways from the stocks on which it is built.-the boat of the largest size belonging to a ship of war; also, an open boat of any size driven by steam, naphtha, electricity, or the like.