Definition of "shield"

Anything that protects or defends; defense; shelter; protection.

1. A broad piece of defensive armor, held in hand, formerly in general use in war, for the protection of the body.  quotations  examples

   Quotations

   • Knock go and come; God's vassals drop and die; And sword and shield, In bloody field, Doth win immortal fame.

     1599, William Shakespeare, Henry V, act III, scene II, line 8

   • The shields used by our Norman ancestors were the triangular or heater shield, the target or buckler, the roundel or rondache, and the pavais, pavache, or tallevas.

     1786, Francis Grose, A Treatise on Ancient Armour and Weapons, page 22

   • My client welcomed the judge […] and they disappeared together into the Ethiopian card-room, which was filled with the assegais and exclamation point shields Mr. Cooke had had made at the sawmill at Beaverton.

     1897 December (indicated as 1898), Winston Churchill, chapter VIII, in The Celebrity: An Episode, New York, N.Y.: The Macmillan Company; London: Macmillan & Co., Ltd.

2. (figurative) One who protects or defends.  quotations  examples

   Quotations

   • Fear not, Abram: I am thy shield, and thy exceeding great reward.

     1611, The Holy Bible, King James Version edition, Genesis 15:1

   • Go muster men. My counsel is my shield; We must be brief when traitors brave the field.

     1592, William Shakespeare, Richard III, act 4, scene 3, line 56

3. (lichenology) In lichens, a hardened cup or disk surrounded by a rim and containing the fructification, or asci.

4. (mining, tunnelling) A framework used to protect workmen in making an adit under ground, and capable of being pushed along as excavation progresses.  quotations  examples

   Quotations

   • The earth was excavated from the sunken cylinder; the shield was inserted into it, and the tunnelling began, the target being Wapping, on the opposite bank. The shield was an iron honeycomb containing thirty-six cells within which men dug the wall of mud before them.

     2012, Andrew Martin, Underground Overground: A passenger's history of the Tube, Profile Books, page 88

5. (science fiction) A field of energy that protects or defends.  quotations  examples

   Quotations

   • Kinetic barriers, colloquially called "shields", provide protection against most mass accelerator weapons. Whether on a starship or a soldier's suit of armor, the basic principle remains the same.Kinetic barriers are repulsive mass effect fields projected from tiny emitters. These shields safely deflect small objects traveling at rapid velocities. This affords protection from bullets and other dangerous projectiles, but still allows the user to sit down without knocking away their chair.

     2008, BioWare, Mass Effect, Redwood City: Electronic Arts, PC, scene: Kinetic Barriers ("Shields") Codex entry

A shape like that of a shield; usually, an inverted triangle with sides that curve inward to form a pointed bottom, commonly used for police identifications and company logos.

1. (heraldry) The escutcheon or field on which are placed the bearings in coats of arms.  quotations  examples

   Quotations

   • The second and third quarters of the shield are indecipherable on the stone but clearer in two other representations of the arms, a painted wooden funeral hatchment for Mary Davie […]

     2012 October 8, Daniel W. Patterson, The True Image: Gravestone Art and the Culture of Scotch Irish Settlers in the Pennsylvania and Carolina Backcountry‎, UNC Press Books, page 141

2. (Scotland, euphemistic, obsolete) A toilet seat.

3. A spot resembling, or having the form of a shield.  quotations  examples

   Quotations

   • Bespotted as with shields of red and black.

     1590, Edmund Spenser, The Faerie Queene

4. (obsolete) A coin, the old French crown, or écu, having on one side the figure of a shield.

5. (transport) A sign or symbol, usually containing numbers and sometimes letters, identifying a highway route.  examples

6. (colloquial, law enforcement) A police badge.  quotations  examples

   Quotations

   • The chief put something in his hand and Bosch looked down to see the gold detective's shield.

     2005, Michael Connelly, The closers: a novel

(geology) A large expanse of exposed stable Precambrian rock.

1. (geology) A wide and relatively low-profiled volcano, usually composed entirely of lava flows.

(figuratively, Scotland, euphemistic, obsolete) A place with a toilet seat: an outhouse; a lavatory.

(automotive, British) Parts at the front and back of a vehicle which are meant to absorb the impact of a collision  examples

(transitive, intransitive) To protect, to defend.  quotations  examples

(UK, intransitive) To shelter; to protect oneself.  quotations  examples

(electricity) To protect from the influence of.  examples