shield

Definitions

General English

General Science

  • noun a large area of very old rocks

Computing

  • noun a metal screen connected to earth, used to prevent harmful voltages or interference reaching sensitive electronic equipment
  • verb to protect a signal or device from external interference or harmful voltages

Construction

  • In excavation, a short, hollow section mounted at the heading end of a jacked pipe or tunnel with a front-leaning plane to deter soil inflow.

Electronics

  • An enclosure, housing, wall, panel, sheet, projection, or other structure or entity which serves to protect from something.
  • A wall or other housing, usually of concrete and/or lead, built around a nuclear reactor to help prevent radiation from escaping. Also, such a shield placed around any source of radiation. Also called shielding (3).

Military

  • noun a piece of metal, plastic or other material, which is designed to be held in front of your body as protection from blows or projectiles
  • noun anything which is used as a shield
  • noun a structure which is fitted to a piece of equipment or machinery, in order to protect the operator from any dangerous effects
  • verb to protect a person by placing something between him and a source of danger

Origin & History of “shield”

Shield goes back to a prehistoric Germanic *skelduz, which also produced German and Dutch schild, Swedish sköld, and Danish skjoldr. this was probably derived from the Germanic base *skel- ‘divide, split, separate’ (source also of English scale, shell, etc), and hence denoted etymologically a ‘flat piece of wood produced by splitting a log, board’. Shelter is probably descended from a compound formed from shield.
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