symplast Syllabification: (sym·plast)Pronunciation: /ˈsimˌplast/Definition of symplast noun Botany a continuous network of interconnected plant cell protoplasts. Derivatives symplasticPronunciation: /simˈplastik/ adjective Origin: 1930s: from German Symplastsymplast in other Oxford dictionaries Definition of symplast in the British & World English dictionary