coniospermous,a.Bot.|ˌkɒnɪəʊˈspɜːməs| [f. as prec. + Gr. -σπερµ-ος, from σπέρµα seed + -ous.] Of fungi: Having spores resembling dust. 1874Cooke Fungi 67 The dusty mass of spores tends more towards the Coniomycetes, this being characterized as the coniospermous sub-family.