mas·​tiff | \ ˈma-stəf How to pronounce mastiff (audio) \

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

Also known as a Cane Corso, Italian mastiffs look like supersized pit bull terriers. Krista Kafer, The Denver Post, "Kafer: Will Aurora be the next Colorado city to ditch its unfair breed ban?," 11 July 2019 Pit bull terriers aren’t different than other powerful and protective breeds such as Rottweilers, Chow Chows, Akitas, shepherds, Doberman pinschers and mastiffs. Krista Kafer, The Denver Post, "Kafer: Will Aurora be the next Colorado city to ditch its unfair breed ban?," 11 July 2019 An enormous mastiff mix dumped at a Florida animal shelter may belong to a deployed service member, the Hernando County Animal Services director said. Tiffini Theisen,, "Florida man dog-sitting for deployed service member may have dumped mastiff off at shelter," 27 June 2019 As champion, Scamp joins the ranks of previous competition winners including Zsa Zsa the English bulldog and Martha the Neapolitan mastiff. Brigit Katz, Smithsonian, "Meet Scamp the Tramp, the World’s Ugliest Dog," 25 June 2019 The actor was also a dad to a bull mastiff named Butkus, who appeared in Rocky and Rocky II. Alexia Fernandez,, "Sylvester Stallone Celebrates the 40th Anniversary of Rocky II: I Am 'Incredibly Grateful'," 17 June 2019 Get a workout at the pingpong table or introduce yourself to co-owner Jay Gordon’s French mastiff. Lisa Boone,, "Four Hours: Shop, dine, chill, repeat at the Row DTLA," 7 June 2019 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

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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Last Updated

7 Aug 2019

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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 How to pronounce mastiff (audio) \

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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