a. A usually rectangular pad of heavy cloth filled with soft material or an arrangement of coiled springs, used as or on a bed.
b. An airtight inflatable pad used as or on a bed or as a cushion.
2. A closely woven mat of brush and poles used to protect an embankment, a dike, or a dam from erosion.
[Middle English materas, mattresse, from Old French materas, from Old Italian materasso and from Medieval Latin matracium, both from Arabic maṭraḥ, place where something is thrown, mat, cushion, from ṭaraḥa, to throw; see ṭrḥ in the Appendix of Semitic 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.