noun

• (clothing, monarchy) A royal, imperial or princely headdress; a diadem.
  "Before so many of Europe's crowns came tumbling off the heads of their royal owners, Continental Europe could show a rich variety in the matter of royal trains."
• (by extension) Any reward of victory or mark of honor.
  "the martyr’s crown"
• (metonymic) The sovereign (in a monarchy), as head of state.
  "A parliament may be diſſolved by the demiſe of the crown."
• (by extension, especially in law) The state, the government (headed by a monarch).
  "Treasure recovered from shipwrecks automatically becomes property of the Crown."

verb

• (medicine) Of a baby, during the birthing process; for the surface of the baby's head to appear in the vaginal opening.
  "The mother was in the second stage of labor and the fetus had just crowned, prompting a round of encouragement from the midwives."
• (transitive) To cause to round upward; to make anything higher at the middle than at the edges, such as the face of a machine pulley.
• (video games) To shoot an opponent in the back of the head with a shotgun in a first-person shooter video game.
• (board games) In checkers, to stack two checkers to indicate that the piece has become a king.
  "“Crown me!” I said, as I moved my checker to the back row."

verb

• (archaic) past participle of crow
  "The cock had crown."

name

• (government) The sovereign of a monarchy; often with reference to that of the Commonwealth realms.
• (government) The government of a monarchy; often with reference to one that is a member of the Commonwealth realms.
• (Canada, law) A Crown attorney.