EphemeropteraPronunciation: /ɪˌfɛməˈrɒptərə, -ˌfiːm-/Definition of Ephemeroptera noun Entomology an order of insects that comprises the mayflies. (ephemeroptera) insects of the order Ephemeroptera; mayflies: various species of ephemeropteraDerivatives ephemeropteran noun & adjective Origin:modern Latin (plural), from Ephemera (genus name) + pteron 'wing'Ephemeroptera in other Oxford dictionaries Definition of Ephemeroptera in the US English dictionary
