sedum Syllabification: (se·dum)Pronunciation: /ˈsēdəm/Definition of sedum noun a widely distributed fleshy-leaved plant with small star-shaped yellow, pink, or white flowers, grown as an ornamental. Genus Sedum, family Crassulaceae: many species, including the stonecrops Origin:from modern Latin, denoting a houseleeksedum in other Oxford dictionaries Definition of sedum in the British & World English dictionary