tr.v. de·terred, de·ter·ring, de·ters
1. To prevent or discourage from acting, as by means of fear or doubt: threats that did not deter her from speaking out; skin chemicals that deter predators.
2. To prevent or discourage (an action or behavior): installed surveillance cameras to deter vandalism.
3. To make less likely or prevent from happening: protocols to deter infection.
[Latin dēterrēre : dē-, de- + terrēre, to frighten.]
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.