ae·​cid·​i·​um | \ ē-ˈsi-dē-əm \

Definition of aecidium

1 plural aecidia\ ē-​ˈsi-​dē-​ə \ : aecium especially : a cup-shaped or spheroidal aecium with a peridial layer
2 capitalized : a form genus of rust fungi having only an aecial stage with toothed cup-shaped peridia

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First Known Use of aecidium

1751, in the meaning defined at sense 2

History and Etymology for aecidium

borrowed from New Latin, irregularly for *oecidium, borrowed from Greek oikídion, diminutive of oîkos “house, abode, room”

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The first known use of aecidium was in 1751

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Cite this Entry

“Aecidium.” Dictionary, Merriam-Webster, Accessed 20 Oct. 2021.

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