noun mas·tiff \ˈmas-təf\

: a type of large, powerful dog

Full 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

Origin of MASTIFF

Middle English mastif, from Medieval Latin mastivus, from Vulgar Latin *masuetivus, from Latin mansuetus tame — more at mansuetude
First Known Use: 14th century
MASTIFF Defined for Kids


noun mas·tiff \ˈma-stəf\

Definition of MASTIFF for Kids

:  a very large powerful dog with a smooth coat


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