The name of a variety of dog of a very old English breed, now seldom seen in its original state of purity. Manwood states that the word is derived from mase thefese, because it is supposed to terrify thieves by its voice, which, when the animal is excited, is fearfully deep and loud. This is the Dogue de forte race of Buffon and the French, the Mastivus of Ray, the Canis Molossus of Linnæus, and the Villaticus or Catenarius of Dr. Caius.
A true-bred mastiff is of considerable size, and very stoutly built. The head is well developed and large, the lips deep and pendulous on each side of the mouth, and the whole aspect noble.
It appears from Claudian and Gratius that the British dogs, mastiffs probably, were highly prised at Rome; and Camden notices the employment of a special officer, Procurator Cynegii, appointed in Britain for superintending the breed of these dogs and their transmission to that city, where they appeared in the combats of animals at the amphitheatre, and sometimes upon occasions even more cruel, for there can be little doubt that they were set to worry those unhappy Christians whom the tyrants of the time ordered to be sewed up in the skins of beasts and then exposed to the attacks of those powerful and savage dogs. Pennant quotes Strabo for the fact that the Gauls trained British mastiffs for war, and used them in their battles. According to Dr. Caius, three were a match for a bear, and four for a lion; but Stow mentions a lion fight with three of these dogs, in which, though two were disabled, and afterward died, the lion was so much harassed that he retreated, and refused to resume the battle.
The mastiff is capable of great attachment, and when kept as a guard is of unfailing vigilance, giving the alarm by its powerful bark, and never ceasing till it has roused the family or secured the intruder. It is now comparatively little used as a watchdog, especially in great towns, where an active police has almost entirely superseded it.