letterbox vs tank

letterbox

noun
  • A hidden container that holds a logbook and rubber stamp, found by following clues as a form of recreation. 

  • A rectangular hole or slot. 

  • A delivery point for mail, a box, compartment or slot for this purpose. 

  • A collection point for mail intended for onward delivery, a secure box or receptacle for this purpose. 

verb
  • To transfer a widescreen motion picture to home video formats while preserving the original aspect ratio, with the placing of black bars above and below the picture area. 

  • To hunt for letterboxes (containers with logbook and rubber stamp) by following clues. 

adj
  • Transferred to home video formats while preserving the original aspect ratio, having black bars above and below the picture area. 

tank

noun
  • An open container or pool for storing water or other liquids. 

  • A prison cell, or prison generally. 

  • A pond, pool, or small lake, natural or artificial. 

  • A closed container for liquids or gases. 

  • A very muscular and physically imposing person. Somebody who is built like a tank. 

  • A small Indian dry measure, averaging 240 grains in weight. 

  • A metaphorical place where a player goes to contemplate a decision; see in the tank. 

  • The fuel reservoir of a vehicle. 

  • By extension a small pond for the same purpose. 

  • An armoured fighting vehicle, armed with a gun, and moving on caterpillar tracks. 

  • a unit or character designed primarily around damage absorption and holding the attention of the enemy (as opposed to dealing damage, healing, or other tasks). 

  • The amount held by a container; a tankful. 

  • A Bombay weight of 72 grains, for pearls. 

  • A large metal container for holding drinking water for animals, usually placed near a wind-driven water pump, in an animal pen or field. 

  • A reservoir or dam. 

verb
  • To put (fuel, etc.) into a tank. 

  • To contemplate a decision for a long time; to go in the tank. 

  • To stand; to tolerate. 

  • To fail or fall (often used in describing the economy or the stock market); to degenerate or decline rapidly; to plummet. 

  • To deliberately lose a sports match with the intent of gaining a perceived future competitive advantage. 

  • To attract the attacks of an enemy target in cooperative team-based combat, so that one's teammates can defeat the enemy in question more efficiently. 

  • To resist damage; to be attacked without being hurt. 

How often have the words letterbox and tank occurred in a corpus of books? (source: Google Ngram Viewer )