v. dis·ap·point·ed, dis·ap·point·ing, dis·ap·points
1. To fail to satisfy the hope, desire, or expectation of.
2. To frustrate or thwart: "I will not disappoint the confidence you have put in me" (Wayne A. Budd).
To cause disappointment.
[Middle English disappointen, from Old French desapointier, to remove from office : des-, dis- + apointer, apointier, to appoint; see APPOINT.]
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.