ter·cen·ten·a·ry (tûr′sĕn-tĕnə-rē, tər-sĕntə-nĕr′ē)
n. pl. ter·cen·ten·a·ries
A 300th anniversary or its celebration.
Of or relating to a span of 300 years or to a 300th anniversary.
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.