exosporium

[ ek-soh-spawr-ee-uh m, -spohr- ]
/ ˌɛk soʊˈspɔr i əm, -ˈspoʊr- /

noun, plural ex·o·spo·ri·a [ek-soh-spawr-ee-uh, -spohr-] /ˌɛk soʊˈspɔr i ə, -ˈspoʊr-/.