cryovolcano UK /ˌkɹaɪ.əʊ.vɒlˈkeɪ.nəʊ/US /ˌkɹaɪ.oʊ.vɑlˈkeɪ.noʊ/ noun1 •A volcano on an icy moon that ejects volatile materials rather than magma. formscryovolcanoes · cryovolcanos