n. pl. ath·er·o·mas or ath·er·o·ma·ta (-mə-tə)
A lipid-containing lesion that forms on the innermost layer of the wall of an artery in atherosclerosis; a plaque.
[Latin athērōma, tumor full of pus that is like gruel, from Greek, from athēra, gruel, variant of atharē, gruel, perhaps of Egyptian origin, or perhaps from an Indo-European adstrate source akin to Hittite ḫattar, a kind of grain or pulse, and Latin ador, emmer.]
ath′er·o·ma·tosis (-tōsĭs) n.
ath′er·oma·tous (-rŏmə-təs, -rōmə-) adj.
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.