verb

• (transitive) To throw (a projectile such as a lance, dart or ball); to hurl; to propel with force.
  "There they were met by four thousand Ha'apa'a warriors, who launched a volley of stones and spears[…]"
• (transitive, obsolete) To pierce with, or as with, a lance.
  "And launch your hearts with lamentable wounds."
• (transitive) To cause (a vessel) to move or slide from the land or a larger vessel into the water; to set afloat.
  "Now when he had left speaking, he said unto Simon, Launch out into the deep, and let down your nets for a draught."
• (transitive) To cause (a rocket, balloon, etc., or the payload thereof) to begin its flight upward from the ground.
  "A cheap rocket that could launch military reconnaisance satellites for developing countries has become involved in a tangled web of Nazi rocket scientists, Penthouse magazine, KGB disinformation, and a treaty reminiscent of the height of colonialism in Africa."

noun

• (nautical) The boat of the largest size and/or of most importance belonging to a ship of war, and often called the "captain's boat" or "captain's launch".
• (nautical) A boat used to convey guests to and from a yacht.
• (nautical) An open boat of any size powered by steam, petrol, electricity, etc.