noun

• (wrestling, professional wrestling) The victory condition of holding the opponent's shoulders on the wrestling mat for a prescribed period of time.
• (informal, in the plural) A leg.
  "I'm not so good on my pins these days."
• (electricity) Any of the individual connecting elements of a multipole electrical connector.
  "The UK standard connector for domestic mains electricity has three pins."
• (US) A simple accessory that can be attached to clothing with a pin or fastener, often round and bearing a design, logo or message, and used for decoration, identification or to show political affiliation, etc.

verb

• (often followed by a preposition such as "to" or "on") To fasten or attach (something) with a pin.
• (chess, usually passive voice) To cause (a piece) to be in a pin.
• (wrestling) To pin down (someone).
  "He pinned his opponent on the mat."
• (graphical user interface, transitive) To attach (an icon, application, message etc.) to another item so that it persists.
  "to pin a folder to the taskbar"

noun

• (organic chemistry) Initialism of preferred IUPAC name.