mastiff

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noun mas·tiff \ˈmas-təf\

Definition of mastiff

  1. :  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

Recent Examples of mastiff from the Web

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.

Illustration of mastiff

Origin and Etymology of mastiff

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


MASTIFF Defined for English Language Learners

mastiff

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noun

Definition of mastiff for English Language Learners

  • : a type of large, powerful dog


MASTIFF Defined for Kids

mastiff

play
noun mas·tiff \ˈma-stəf\

Definition of mastiff for Students

  1. :  a very large powerful dog with a smooth coat


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