gametophyteEnglishOxford New American Dictionarygametophyte /ɡəˈmēdəˌfīt, ɡəˈmidəˌfaɪt / ▸ noun Botany (in the life cycle of plants with alternating generations) the gamete-producing and usually haploid phase, producing the zygote from which the sporophyte arises. It is the dominant form in bryophytes. – DERIVATIVES gametophytic /ɡəˌmētəˈfitik/ adjective