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ath·er·o·ma

(ăth′ə-rōmə)

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·tosis (-tōsĭs) n.

ath′er·oma·tous (-rŏmə-təs, -rōmə-) adj.

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.

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