mas·​tiff | \ ˈmas-təf \

Definition of mastiff

: 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

Illustration of mastiff

Examples of mastiff in a Sentence

Recent Examples on the Web

Guarding the prized flock are nine Spanish mastiffs, worth $2,500 apiece. Cori Petersen, WSJ, "Wolves Attack Wisconsin With Washington’s Help," 27 July 2018 And a Chinese zoo tried to pass off a Tibetan mastiff dog as an actually lion. Fox News, "Trump touts economy in the heartland," 27 July 2018 David and Rachel share their home with an 11-year-old mastiff, an 8-year-old Labrador, and a 7-year-old catahoula leopard dog. Cathy M. Rosenthal, San Antonio Express-News, "Social media great at helping lost pets get home again," 15 June 2018 This was the second mastiff wolves had eaten on their property. Cori Petersen, WSJ, "Wolves Attack Wisconsin With Washington’s Help," 27 July 2018 Last year, animal rights groups protested after the Oregon Court of Appeals upheld a decision by a state judge requiring a couple to have their Tibetan mastiffs debarked. Lisa Gutierrez, kansascity, "Breeder 'debarked' dogs by shoving a pipe down their throats, Penn. authorities say," 30 May 2018 The short-nosed breeds include bulldogs, boxers, pugs, Boston terriers, Pekingese, mastiffs, shih tzus and others. Martine Powers, Washington Post, "More dogs die on United than on any other airline. Here’s why.," 4 Apr. 2018 One new and increasing potential danger are the farmers’ mastiff dogs, Smith explains. National Geographic, "Rare Bunny-Faced Mammal Captured on Video," 14 June 2018 As floats, bands, clowns, queens and even a bull mastiff march down the streets of Portland, drivers, buses, MAX trains and other modes of transportation get delayed. Rosemarie Stein,, "Traffic advisory: How to get around the 2018 Rose Festival Parade," 8 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mastiff.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of mastiff

14th century, in the meaning defined above

History and Etymology for mastiff

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

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The first known use of mastiff was in the 14th century

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English Language Learners Definition of mastiff

: a type of large, powerful dog


mas·​tiff | \ ˈma-stəf \

Kids Definition of mastiff

: a very large powerful dog with a smooth coat

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More from Merriam-Webster on mastiff

Spanish Central: Translation of mastiff

Nglish: Translation of mastiff for Spanish Speakers Encyclopedia article about mastiff

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