tr.v. en·joined, en·join·ing, en·joins
a. To direct (a person) to do something; order or urge: The doctor enjoined the patient to walk daily.
b. To require or impose (an action or behavior, for example) with authority and emphasis; prescribe.
2. To prohibit or forbid: The judge enjoined the merger of the firms. The court enjoined the company from merging with its competitor.
[Middle English enjoinen, from Old French enjoindre, from Latin iniungere : in-, causative pref.; see EN-1 + iungere, to join; see yeug- 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.