mastiff

noun

mas·​tiff ˈma-stəf 

: any of a breed of very large massive powerful smooth-coated dogs that are apricot, fawn, or brindle and are often used as guard dogs

Illustration of mastiff

Examples of mastiff in a Sentence

Recent Examples on the Web

Other dogs listed by the American Kennel Club as the best guardians include the Rottweiler, most shepherd dogs, the Staffordshire bull terrier, volpino Italiano, and Tibetan mastiff among others. —Marco Rubio, Newsweek, 1 Nov. 2024

The Tibetan mastiff is often considered the most expensive dog since the breed has sold for up to millions of dollars. —Olivia Munson, USA TODAY, 17 Aug. 2024

In 2011, another Tibetan mastiff puppy sold for $1.5 million, according to NBC News, which reported the animal was the most expensive dog sold at the time. —Olivia Munson, USA TODAY, 17 Aug. 2024

The big, robust mastiff in Guercino’s portrait is posed on a stately balustrade next to a sturdy classical column. —Christopher Knight, Los Angeles Times, 13 Aug. 2024

Word History

Etymology

Middle English mastif, from Medieval Latin mastivus, from Vulgar Latin *masuetivus, from Latin mansuetus tame — more at mansuetude

First Known Use

14th century, in the meaning defined above

Kids Definition

mastiff

noun

mas·​tiff ˈmas-təf 

: any of a breed of large powerful smooth-coated dogs often used as watchdogs and guard dogs