su·per·sede also su·per·cede (s′pər-sēd)
tr.v. su·per·sed·ed, su·per·sed·ing, su·per·sedes or su·per·ced·ed or su·per·ced·ing or su·per·cedes
1. To take the place of; replace or supplant: "[Dean] Acheson's conversion, that military force should supersede diplomatic response as the core of U.S. foreign policy, would reverberate across generations" (James Carroll).
2. To take the place of (a person), as in an office or position; succeed. See Synonyms at replace.
[Late Middle English (Scottish) superceden, to postpone, defer, from Old French superceder, from Latin supersedēre, to sit on top of, abstain from : super-, super- + sedēre, to sit; see sed- in the Appendix of Indo-European roots.]
su′per·seder, su′per·ceder n.
su′per·session, su′per·cession (-sĕshən) n.
Usage Note: Supersede is commonly spelled supercede, probably by influence of words like accede and intercede. The spelling with a c has been in existence for 300 years and has traditionally been considered an error, but it appears so widely in books and other edited publications that this spelling must be considered standard.
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.