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Definitions

General English

General Science

  • noun the set of words that appear at the top of each page of a document, e.g. title, author’s name or page number.

Agriculture

  • noun a machine which removes the seed heads from plants.

Cars & Driving

  • noun a part at the top of another part

Computing

  • noun a packet of data that is sent before a transmission to provide information on destination and routing
  • noun information at the beginning of a list of data relating to the rest of the data
  • noun a section of words at the top of a page of a document, giving e.g. the title, author’s name or page number.

Construction

  • A rectangular masonry unit laid across the thickness of a wall, so as to expose its end(s).
  • A member extending horizontally between two joists to support tailpieces.
  • In piping, a chamber, pipe, or conduit having several openings through which it collects or distributes material from other pipes or conduits. See also manifold.
  • The wood surrounding an area of asphaltic concrete paving.

Electronics

  • That which appears at the start of something, and which serves to identify, describe, route, control, and so on.
  • In a file, a region which has information such as the name, size, and date created.
  • In communications, the first part of a message, packet, or the like. A header may contain information such as the originating and destination stations, the length, protocol utilized, and so on.
  • In word processing, a text which appears at the top of one or more pages. Such text may appear only on a give page, specified pages, even pages, odd pages, or on every page. Also called page header.
  • A mounting plate, usually made of glass, through which one or more insulated terminals or leads originating from a hermetically sealed component, device, or piece of equipment are passed. Utilized, for instance, to expose the leads of a transistor, relay, tube, or the like. Such a header also provides support for said terminals or leads.

Information & Library Science

  • noun a piece of text that appears at the very top of each page, containing e.g. the chapter name and the page number.
  • noun the beginning of an e-mail message with full information about the recipient’s address, sender’s name and address and any delivery options

Real Estate

  • noun a brick or stone positioned crosswise in a wall and level with its outer surface.

Slang

  • noun an unhinged, deranged or unstable person. A version of the earlier headcase, recorded in 2004.
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