What does conidia mean?
Conidia are asexual, non-motile spores produced by a wide range of fungi — including familiar genera such as Penicillium and Aspergillus — and by certain other organisms. Unlike spores formed through sexual reproduction, conidia arise purely by mitotic cell division, usually at the tips or along the sides of specialized hyphal branches called conidiophores, which means each one is essentially a genetic clone of its parent. Light, dry, and produced in enormous numbers, they are readily dispersed by air currents and water, making them the principal agents by which many molds colonize new food sources and spread disease among crops. Because of this, conidia feature prominently in mycology, agriculture, and medicine, where identifying their shape and arrangement is often key to diagnosing a fungal species. The term is technical in register, appearing chiefly in scientific literature rather than everyday speech, and takes the singular form conidium when a single spore is meant.
nounConidia are asexual, non-motile spores produced by many fungi and some other organisms, typically formed at the tips or sides of specialized hyphae and dispersed by wind, water, or other means to colonize new substrates.
- Asexual fungal spores produced at the tips or sides of hyphae (or conidiophores) and dispersed for reproduction without sexual fusion.
"The fungus spreads rapidly across the crop as its conidia are carried on the summer breeze."
"Penicillium releases vast numbers of conidia, giving mold colonies their powdery blue-green appearance."
"Under the microscope, the lab identified chains of conidia characteristic of Aspergillus species."
Conidia is itself the plural of the singular noun 'conidium'; treat it as plural in formal scientific writing, e.g. 'the conidia were examined under high magnification'.
"Thousands of conidia drifted from the sporulating colony onto the culture plate below."
Every puff of 'mold dust' you see drifting from an old loaf is millions of conidia — each one a complete, ready-to-grow clone of its parent.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of conidia
The word comes from modern Latin 'conidium', itself borrowed from Greek 'konis' meaning 'dust' combined with the diminutive suffix '-idion' — so literally a 'little dust particle', a fitting description of these fine, powder-like spores. It was coined in the nineteenth century as mycologists began systematically classifying fungal reproductive structures. The same Greek root survives in other scientific vocabulary, such as 'conidiophore', the specialized stalk that bears conidia.
Related word forms
How conidia is actually used
Strictly speaking, 'conidia' is the plural form; the singular is 'conidium'. The word belongs almost entirely to scientific and technical register — mycology, plant pathology, microbiology — and is rare in general conversation. It should be treated as plural in formal writing ('the conidia were observed'), though it may occasionally be used loosely as a mass noun when referring to spores collectively.
Easily confused with conidia
Sporangia are sac-like structures that enclose spores internally, whereas conidia are exposed spores borne externally on conidiophores.
Zygospores are sexual spores formed by the fusion of gametes, while conidia arise asexually by mitosis alone.