1. The ability to acquire, understand, and use knowledge: a person of extraordinary intelligence.
a. Information, especially secret information gathered about an actual or potential enemy or adversary.
b. The gathering of such information: "Corporate intelligence relies on a slew of tools, some sophisticated, many quite basic" (Neil King and Jess Bravin).
c. An agency or organization whose purpose is to gather such information: an officer from military intelligence.
3. An intelligent, incorporeal being, especially an angel.
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.