guard dog

American  

Or guarddog

noun

• guard dogs
  plural

1. a large, aggressive dog, as a German shepherd or Doberman pinscher, trained to guard persons or property and often to attack or restrain on command.

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Other Word Forms

Noun Inflected Forms

• guard dogs
  plural

Etymology

Origin of guard dog

First recorded in 1790–1800

Example Sentences

See Examples For:

guard dog

The opposite of a guard dog: Golden retriever begs to play with intruder in San Diego break-in.

From MarketWatch ● Sep. 17, 2026

The intruder might have been deterred by the couple’s two dogs — except that neither canine acted like a traditional guard dog.

From Los Angeles Times ● Sep. 16, 2026

Anatol Ward, a Tokyo resident in his 50s, said the robot reminded him of a guard dog.

From Barron's ● Jan. 30, 2026

But now, Young and a colleague have published new research that suggests farmers could turn to an ancient human ally, the guard dog, to scare grizzlies away cheaply and effectively.

From Science Magazine ● Apr. 11, 2024

The canines on these hummers were as big as the canines on any guard dog you’ll ever see, and that was a rude awakening.

From "The Hot Zone" by Richard Preston

Related Words

• attack dog