ae·ci·um (ēsē-əm, ēshē-)
n. pl. ae·ci·a (-sē-ə, -shē-ə)
A cuplike structure of some rust fungi that contains chains of aeciospores.
[New Latin, from Greek aikiā, injury, from aikēs, unseemly, injurious : a-, not; see A-1 + eikenai, to seem, be seemly.]
aeci·al (ēsē-əl, -shē-) adj.
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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.