caladiumPronunciation: /kəˈleɪdɪəm/Definition of caladium noun (plural caladiums) a tropical South American plant of the arum family, which is cultivated for its brilliantly coloured ornamental foliage. Genus Caladium, family Araceae Origin:modern Latin, from Malay keladicaladium in other Oxford dictionaries Definition of caladium in the US English dictionary