tier 1 (tîr)
1. One of a series of rows placed one above another: a stadium with four tiers of seats.
2. A rank or class.
tr. & intr.v. tiered, tier·ing, tiers
To arrange (something) into or rise in tiers: tier a wedding cake; balconies that tier upward.
[Middle English tire, row, rank, from Old French, from tirer, to draw out; see TIRADE.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 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.