A dog of a large powerful breed developed in England as a guard dog, having a large head, short black muzzle, and short often fawn-colored coat.
[Middle English mastif, alteration (perhaps influenced by Old French mestif, mongrel) of Old French mastin, from Vulgar Latin *(canis) mānsuētīnus, tame (dog), from Latin mānsuētus, past participle of mānsuēscere, to tame : manus, hand; see man-2 in the Appendix of Indo-European roots + suēscere, to accustom; see s(w)e- in the Appendix of Indo-European roots.]
(click for a larger image)mastiff
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