| COCCIDIUM | • coccidium n. Synonym of coccidian. • COCCIDIUM n. a parasitic protozoan. |
| CORMIDIUM | • cormidium n. (Zoology) The colonial body of a compound animal. • CORMIDIUM n. (Latin) the assemblage of individuals dangling in clusters from the main stem of pelagic siphonophores. |
| CTENIDIUM | • ctenidium n. (Zoology) A respiratory system, in the form of a comb, in some molluscs. • ctenidium n. (Zoology) A row of spines in some insects. • CTENIDIUM n. (Greek) a comblike anatomical structure. |
| CYMBIDIUM | • cymbidium n. (Botany) Any orchid of the genus Cymbidium. • Cymbidium prop.n. A taxonomic genus within the family Orchidaceae – boat orchids. • CYMBIDIUM n. a kind of tropical orchid. |
| ONCIDIUMS | • oncidiums n. Plural of oncidium. • ONCIDIUM n. any of a genus of tropical orchidaceous plants. |
| PERIDIUMS | • peridiums n. Plural of peridium. • PERIDIUM n. the outer coating of the spore carrier of a fungus. |
| PRESIDIUM | • presidium n. A permanent executive committee, used primarily in Communist countries, with the power to act for a… • presidium n. Such an executive committee headed by the President of the Supreme Soviet. • PRESIDIUM n. (Latin) a standing committee in the former Soviet Union, also PRAESIDIUM. |
| PYCNIDIUM | • pycnidium n. In certain fungi, a flask-shaped cavity from the surface of the inner walls of which spores are produced. • PYCNIDIUM n. a spore-bearing organ in some fungi. |
| RHIPIDIUM | • rhipidium n. (Botany) A scorpioid cyme whose successive pedicels follow a zigzag path on the same plane. • RHIPIDIUM n. a fan-shaped cymose inflorescence. |
| RUBIDIUMS | • rubidiums n. Plural of rubidium. • RUBIDIUM n. a metallic element. |
| SPORIDIUM | • sporidium n. (Botany) A secondary spore borne on a promycelium, or a filament produced from a spore, in certain kinds… • sporidium n. An ascospore. • sporidium n. Any spore. |
| VENIDIUMS | • venidiums n. Plural of venidium. • VENIDIUM n. a plant native to South Africa with yellow or cream flowers, aka Cape Daisy. |