intr.v. eaves·dropped, eaves·drop·ping, eaves·drops
1. To listen secretly to the private conversation of others.
2. To gain access to private electronic communications, as through wiretapping or the interception of email or phone calls.
[Probably back-formation from eavesdropper, one who eavesdrops, from Middle English evesdropper, from evesdrop, place where water falls from the eaves, from Old English yfesdrype; see upo in the Appendix of Indo-European roots.]
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.