deck / dek/ • n. 1. a structure of planks or plates, approximately horizontal, extending across a ship or boat at any of various levels, esp. one of those at the highest level and open to the weather. ∎ a floor or platform resembling or compared to a ship's deck, esp. the floor of a pier or a platform for sunbathing. ∎ a platformlike structure, typically made of lumber and unroofed, attached to a house or other building. ∎ a level of a large, open building, esp. a sports stadium. ∎ (the deck) inf. the ground or floor: there was a thud when I hit the deck. ∎ the flat part of a skateboard or snowboard.2. a component or unit in sound-reproduction equipment that incorporates a playing or recording mechanism for discs or tapes: a tape deck.3. a pack of cards. ∎ inf. a packet of narcotics.• v. [tr.] 1. (usu. be decked) decorate or adorn brightly or festively: Ingrid was decked out in her Sunday best.2. inf. knock (someone) to the ground with a punch.PHRASES: below decks see below decks.clear the decks see clear.not playing with a full deck inf. mentally deficient.on deck on or onto a ship's main deck. ∎ Baseball next to hit in the batting order. ∎ fig. ready for action or work.DERIVATIVES: decked adj.ORIGIN: late Middle English: from Middle Dutch dec ‘covering, roof, cloak,’ dekken ‘to cover.’ Originally denoting canvas used to make a covering (esp. on a ship), the term came to mean the covering itself, later denoting a solid surface serving as roof and floor.