The story
- Ancient Greek · derived fromοἰκίδιον
- Ancient Greek · derived fromαἰκίᾱ“injury”
- New Latin · borrowed fromaecidium
- English todayaecidium
From New Latin aecidium, the diminutive form of Ancient Greek αἰκίᾱ (aikíā, “injury”). However Merriam-Webster takes the origin from Ancient Greek οἰκίδιον (oikídion) and refers to the botanist John Hill, in his A General Natural History, or New and Accurate Descriptions of the Animals, Vegetables, and Minerals, of the Different Parts of the World, vol. II, A History of Plants (London: Printed for Thomas Osborne, 1751), p. 64: "We have called this genus, distinguished by its peculiar cells, Æcidium, from the Greek οικιδιον, cellula." Compare also many other fungal spore-related terms in -idium, most coined after this one.
Words from the same roots
Etymology from Wiktionary, CC BY-SA 4.0.