aecidium

noun

ae·​cid·​i·​um

ē-ˈsi-dē-əm

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

Word History

Etymology

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

First Known Use

1751, in the meaning defined at sense 2

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