case vs letterbox

case

noun
  • A box, sheath, or covering generally. 

  • An instance of a specific condition or set of symptoms. 

  • A small fissure which admits water into the workings. 

  • A box that contains or can contain a number of identical items of manufacture. 

  • A thin layer of harder metal on the surface of an object whose deeper metal is allowed to remain soft. 

  • The outer covering or framework of a piece of apparatus such as a computer. 

  • A section of code representing one of the actions of a conditional switch. 

  • Grammatical cases and their meanings taken either as a topic in general or within a specific language. 

  • A legal proceeding, lawsuit. 

  • A piece of work, specifically defined within a profession. 

  • An instance or event as a topic of study. 

  • A specific inflection of a word (particularly a noun, pronoun, or adjective) depending on its function in the sentence. 

  • A suitcase. 

  • A shallow tray divided into compartments or "boxes" for holding type, traditionally arranged in sets of two, the "upper case" (containing capitals, small capitals, accented) and "lower case" (small letters, figures, punctuation marks, quadrats, and spaces). 

  • An actual event, situation, or fact. 

  • A piece of luggage that can be used to transport an apparatus such as a sewing machine. 

  • An enclosing frame or casing. 

  • A cardboard box that holds (usually 24) beer bottles or cans. 

  • Four of a kind. 

  • A piece of furniture, constructed partially of transparent glass or plastic, within which items can be displayed. 

  • The nature of a piece of alphabetic type, whether a “capital” (upper case) or “small” (lower case) letter. 

  • A unit of liquid measure used to measure sales in the beverage industry, equivalent to 192 fluid ounces. 

adj
  • The last remaining card of a particular rank. 

verb
  • To survey (a building or other location) surreptitiously, as in preparation for a robbery. 

  • To place (an item or items of manufacture) into a box, as in preparation for shipment. 

  • To cover or protect with, or as if with, a case; to enclose. 

letterbox

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

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

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

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. 

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