red gum noun8 •Any of several species of trees found in Australia. •Corymbia calophylla (marri), native to Western Australia, with red gum effusions. •Eucalyptus camaldulensis (Murray red gum, river red gum), a eucalyptus tree with red wood. •Eucalyptus macrorhyncha (red stringybark, Cannon's stringybark, capertee stringybark) •Eucalyptus tereticornis (forest red gum), with red wood. •A tree of the hazel family, of species Liquidambar styraciflua, found in North America. •A rash in infants marked by red or sometimes whitish papules surrounded by reddish halos and popularly associated with teething distress; strophulus. •rust on grain formsred gums