Definition of aecium in English:

aecium

noun

Mycology
  • A fruiting body produced on the mycelium of a rust fungus at a particular stage in its life cycle (especially, in heteroecious species, that occurring on an alternate host), within which aeciospores are produced.

Origin

Early 20th century. Shortened from aecidium, with omission of the medial syllable.

Pronunciation:

aecium

/ˈiːsɪəm/