guard

UK: /ˈgɑː^rd/ US: /gɑrd/ ,(gärd)

WordReference Random House Learner's Dictionary of American English © 2025

guard /gɑrd/   v. 

1. to keep safe from harm or danger;
   protect:
   [~ + object] The dog guarded the house when no one was home.
2. to keep under close watch, as in order to prevent escape:
   [~ + object] The police officers guarded the prisoner.
3. to keep under control as a matter of caution:
   [~ + object] to guard one's temper.
4. to keep secret;
   protect or hide:
   [~ + object] guarded the secrets of his business.
5. to provide or equip with some safeguard or protection: [~ + object]
   This ingredient guards your teeth against decay.
   [~ + against]
   The mouthwash guards against bad breath.
6. Sport [~ (+ against) + object] to position oneself in some sport so as to obstruct or impede the movement or progress of (an opponent on offense).
7. to provide means of protection:
   [~ + against] The computer program should guard against errors.

n. 

8. [countable] a person or group that guards, as one that keeps watch over prisoners or property.
9. an act of guarding;
   a close watch:
   [uncountable] under armed guard.
10. a device, appliance, or attachment that prevents or minimizes injury, loss, etc.:
    [countable] a guard for a goalie in hockey.
11. Sport
    • [countable] either of the football linemen stationed between a tackle and the center, or either of the basketball players stationed in the backcourt.
    • [uncountable] the position played by this player:
      He played guard.
12. British Terms [countable] a railway conductor.

Idioms

13. Idioms off (one's) guard, unprepared;
    unwary:
    caught off guard.
14. Idioms on (one's) guard, watching;
    vigilant;
    wary.
15. Idioms stand guard over, [~ + object] to watch over;
    protect:
    stood guard over their wounded comrade.

guard•er, n. [countable]

WordReference Random House Unabridged Dictionary of American English © 2025

guard  (gärd), v.t. 

1. to keep safe from harm or danger;
   protect;
   watch over:
   to guard the ruler.
2. to keep under close watch in order to prevent escape, misconduct, etc.:
   to guard a prisoner.
3. to keep under control or restraint as a matter of caution or prudence:
   to guard one's temper.
4. to provide or equip with some safeguard or protective appliance, as to prevent loss, injury, etc.
5. Sport to position oneself so as to obstruct or impede the movement or progress of (an opponent on offense):
   The linebacker moved to his right to guard the end going out for a pass.
6. Chess to protect (a piece or a square) by placing a piece in a supportive or defensive position relative to it.

v.i. 

7. to take precautions (usually fol. by against):
   to guard against errors.
8. to give protection;
   keep watch;
   be watchful.

n. 

9. a person or group of persons that guards, protects, or keeps a protective or restraining watch.
10. a person who keeps watch over prisoners or others under restraint.
11. a body of people, esp. soldiers, charged with guarding a place from disturbance, theft, fire, etc.
12. a close watch, as over a prisoner or other person under restraint:
    to be kept under guard.
13. a device, appliance, or attachment that prevents injury, loss, etc.
14. something intended or serving to guard or protect;
    safeguard:
    insurance as a guard against disasters.
15. a posture of defense or readiness, as in fencing, boxing, or bayonet drill.
16. Sport [Football.]
    • either of the linemen stationed between a tackle and the center.
    • the position played by this lineman.
17. [Basketball.] either of the players stationed in the backcourt.
18. Chess, Games a piece that supports or defends another.
19. Games [Cards.] a low card that is held with a high card of the same suit and that enables the holder to save the high card for a later trick.
20. British Terms a railroad conductor.
21. Military Guards, the name of certain bodies of troops in the British army.
22. Idioms off guard, unprepared;
    unwary:
    The blow from behind caught him off guard.
    Also, off one's guard. 
23. Idioms on guard, vigilant;
    wary:
    on guard against dishonest merchants.
    Also, on one's guard. 
24. Idioms stand guard over, to watch over;
    protect:
    The dog stood guard over his wounded master.

• Gmc; see ward
• Old French g(u)arde, noun, nominal derivative of g(u)arder (verb, verbal)
• late Middle English garde guardianship 1375–1425

guard′a•ble, adj. 
guard′er, n. 
guard′less, adj. 
guard′like′, adj. 
Synonyms

• 1. shield, shelter, safeguard; preserve, save. See defend. 
• 3. hold, watch.
• 9. defender, protector; watchman, guardian; guardsman, sentry, sentinel, patrol.
• 14. defense, protection, aegis, security, safety; bulwark, shield.

Antonyms

• 1. attack.

Collins Concise English Dictionary © HarperCollins Publishers::

guard / ɡɑːd/ verb

1. to watch over or shield (a person or thing) from danger or harm; protect
2. to keep watch over (a prisoner or other potentially dangerous person or thing), as to prevent escape
3. (transitive) to control: to guard one's tongue
4. (intransitive) usually followed by against: to take precautions
5. to control entrance and exit through (a gate, door, etc)
6. (transitive) to provide (machinery, etc) with a device to protect the operator
7. (transitive) to protect or cover (a chess man or card) with another
8. to protect or cover (a stone or bowl) by placing one's own stone or bowl between it and another player

noun

1. a person or group that keeps a protecting, supervising, or restraining watch or control over people, such as prisoners, things, etc
   Related adjective(s): custodial
2. a person or group of people, such as soldiers, who form a ceremonial escort
3. the official in charge of a train
4. the act or duty of protecting, restraining, or supervising
5. (as modifier): guard duty
6. 
   another word for garda
7. a device, part, or attachment on an object, such as a weapon or machine tool, designed to protect the user against injury, as on the hilt of a sword or the trigger of a firearm
8. anything that provides or is intended to provide protection: a guard against infection
9. See guard ring
10. an article of light tough material worn to protect any of various parts of the body
11. the posture of defence or readiness in fencing, boxing, cricket, etc
12. mount guard ⇒ (of a sentry) to begin to keep watch
13. (with over) to take up a protective or defensive stance (over something)
14. off one's guard ⇒ having one's defences down; unprepared
15. on one's guard ⇒ prepared to face danger, difficulties, etc
16. stand guard ⇒ (of a military sentry, etc) to keep watch

Etymology: 15th Century: from Old French garde, from garder to protect, of Germanic origin; compare Spanish guardar; see ward

ˈguarder noun