ar·che·spore \ˈärkə̇ˌspō(ə)r\noun orar·che·spo·ri·um\ˌ ̷ ̷ ̷ ̷ˈspōrēəm\ (pluralarche·spores \-rz\ ; orarchespo·ria \-ōrēə\) Etymology: New Latin archesporium, from arche- + -sporium : the cell or group of cells from which spore mother cells develop (as those from which the microspores develop in the pollen sac or the megaspore in the ovule • ar·che·spo·ri·al\| ̷ ̷ ̷ ̷|spōrēəl\adjective