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noun \ˈgärd\

Simple Definition of guard

  • : a state in which someone is carefully looking for possible danger, threats, problems, etc.

  • : a person whose job or duty is to watch and protect someone or something

  • : a group of people (such as soldiers) who protect a person or place

Source: Merriam-Webster's Learner's Dictionary

Full Definition of guard

  1. 1 :  one assigned to protect or oversee another: as a :  a person or a body of persons on sentinel duty b plural :  troops attached to the person of the sovereign c British :  conductor b

  2. 2 a :  a defensive state or attitude <asked him out when his guard was down> b :  a defensive position (as in boxing)

  3. 3 a :  the act or duty of protecting or defending b :  the state of being protected :  protection

  4. 4 :  a protective or safety device; specifically :  a device for protecting a machine part or the operator of a machine

  5. 5 archaic :  precaution

  6. 6 a :  a position or player next to the center in a football line b :  a player stationed in the backcourt in basketball

off guard

  1. :  in an unprepared or unsuspecting state

on guard

  1. :  defensively watchful :  alert

Examples of guard in a sentence

  1. There were dozens of police officers standing guard along the parade route.

  2. Tourists gather every day to watch the changing of the guard at Buckingham Palace.

  3. The guard must be in place before operating the meat slicer.

Origin and Etymology of guard

Middle English garde, from Anglo-French garde, guarde, warde, from garder, guarder, warder, to guard, defend, of Germanic origin; akin to Old High German wartēn to watch, take care — more at ward

First Known Use: 15th century




Simple Definition of guard

  • : to watch (someone) in order to prevent escape

  • : to protect (someone or something) from danger or attack

  • : to be careful about not telling or talking about (something, such as a secret)

Source: Merriam-Webster's Learner's Dictionary

Full Definition of guard

  1. transitive verb
  2. 1 :  to protect an edge of with an ornamental border

  3. 2 a :  to protect from danger especially by watchful attention :  make secure <police guarding our cities> b :  to stand at the entrance of as if on guard or as a barrier c :  to tend to carefully :  preserve, protect <guarded their privacy>

  4. 3 archaic :  escort

  5. 4 a :  to watch over so as to prevent escape, disclosure, or indiscretion b :  to attempt to prevent (an opponent) from playing effectively or scoring

  6. intransitive verb
  7. :  to watch by way of caution or defense :  stand guard



Examples of guard in a sentence

  1. Two policemen were assigned to guard the prisoner.

  2. A tank guarded the bridge from enemy attack.

  3. A police officer was stationed outside to guard the door.

  4. They jealously guard their secrets.

  5. Her whereabouts are a tightly guarded secret.


First Known Use of guard


Synonym Discussion of guard

defend, protect, shield, guard, safeguard mean to keep secure from danger or against attack. defend denotes warding off actual or threatened attack <defend the country>. protect implies the use of something (as a covering) as a bar to the admission or impact of what may attack or injure <a hard hat to protect your head>. shield suggests protective intervention in imminent danger or actual attack <shielded her eyes from the sun with her hand>. guard implies protecting with vigilance and force against expected danger <White House entrances are well guarded>. safeguard implies taking precautionary protective measures against merely possible danger <our civil liberties must be safeguarded>.

GUARD Defined for Kids



noun \ˈgärd\

Definition of guard for Students

  1. 1 :  a person or a body of persons that guards against injury or danger <the palace guard>

  2. 2 :  the act or duty of keeping watch <An officer stood guard outside.>

  3. 3 :  a device giving protection <a mouth guard>




Definition of guard for Students



  1. 1 :  to protect from danger :  defend

  2. 2 :  to watch over so as to prevent escape <guard a prisoner>

  3. 3 :  to keep careful watch for in order to prevent <I try to guard against mistakes.>

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