1. The forward, projecting part of the head of certain animals, such as dogs, including the mouth, nose, and jaws; the snout.
2. A device that is fitted over an animal's snout, often used to prevent biting or eating.
3. The forward, discharging end of the barrel of a firearm.
4. A restraint on free movement or expression: had a muzzle put on their high spirits.
tr.v. muz·zled, muz·zling, muz·zles
1. To put a muzzle on (an animal).
2. To restrain from expression: tried to muzzle the opposition.
[Middle English mosel, from Old French musel, from Medieval Latin mūsellum, diminutive of mūsus, snout, from Latin mūsum.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.