ˈmastə̇f, -aas-, -ais-, sometimes -ȧs- noun
( -s )
Etymology: Middle English mastif, modification (influenced by Middle English -if -ive) of Middle French mastin, from (assumed) Vulgar Latin mansuetinus, from Latin mansuetus tame — more at mansuete
: a very large powerful deep-chested smooth-coated dog of a very old breed used chiefly as a watchdog and guard dog
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