noun🔗ShareマスティフOne of an old breed of powerful, deep-chested, and smooth-coated dogs, used chiefly as watchdogs and guard dogs."The family felt safer knowing their large mastiff patrolled the yard at night. "家族は、大きなマスティフが夜に庭をパトロールしているのを知って、より安全だと感じました。animaltypeChat with AIVocabulary GamePractice Reading