1. A horizontal beam or bar held up by two pairs of divergent legs and used as a support.
2. A framework consisting of slanted braces and horizontal crosspieces supporting a bridge or causeway.
[Middle English trestel, from Old French, alteration of Vulgar Latin *trāstellum, trānstellum, diminutive of Latin trānstrum, beam; see TRANSOM.]
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.