intr.v. com·plained, com·plain·ing, com·plains
1. To express feelings of pain, dissatisfaction, or resentment.
2. To make a formal accusation or bring a formal charge; file a complaint.
[Middle English compleinen, from Old French complaindre, complaign-, from Vulgar Latin *complangere : Latin com-, intensive pref.; see COM- + Latin plangere, to lament; see plāk-2 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.