1. Of, relating to, or suggestive of an empire or a sovereign, especially an emperor or empress: imperial rule; the imperial palace.
2. Ruling over extensive territories or over colonies or dependencies: imperial nations.
a. Having supreme authority; sovereign.
b. Regal; majestic.
4. Outstanding in size or quality.
5. Of or belonging to the British Imperial System of weights and measures.
1. An emperor or empress.
2. The top of a carriage.
3. Something outstanding in size or quality.
4. A variable size of paper, usually 23 by 33 inches (55.8 by 83.8 centimeters).
5. A pointed beard grown from the lower lip and chin.
[Middle English, from Old French, from Latin imperiālis, from imperium, command; see EMPIRE. N., sense 5, after the beard of Napoleon III.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 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.