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dia·per (dīpər, dīə-pər)
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n.
1.
a. A folded piece of absorbent material, such as paper or cloth, that is placed between a baby's legs and fastened at the waist to contain excretions.
b. A similar piece of material, worn by incontinent adults.
2.
a. A pattern composed of small, regularly repeated geometric motifs, usually diamonds or lozenges, used to decorate a surface.
b. A white cotton or linen fabric having such a pattern.
c. A piece of such fabric.
tr.v. dia·pered, dia·per·ing, dia·pers
1. To put a diaper on.
2. To weave or decorate in a diaper pattern.

[Middle English, textile with a diaper pattern, from Old French diapre, variant of diaspre, from Medieval Latin diasprum, from Medieval Greek diaspros, pure white, of white interspersed with other colors (sense uncertain) : Greek dia-, dia- + Late Greek aspros, white (from aspron, silver denarius (originally *“new, unworn coin”), from earlier Late Greek aspros, rough, from Latin asper, rough, unworn (used of new coins whose relief had not yet been worn smooth)).]
(click for a larger image)
diaper
roofing pattern on a building in Obernai, in the Alsace region of France

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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:

    Indo-European Roots

    Semitic Roots

    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.