en- 1 or em- or in-
a. To put into or onto: encapsulate.
b. To go into or onto: enplane.
2. To cover or provide with: enrobe.
3. To cause to be: endear.
4. Thoroughly. Used often as an intensive: entangle.
[Middle English, from Old French, from Latin in-, in; see en 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.