blackbutt /ˈblakbʌt/ noun1 •(Australia) Any of several Australian eucalyptus trees with a dark fibrous bark towards the base of the trunk, especially Eucalyptus pilularis, but also Eucalyptus zopherophloia and Eucalyptus todtiana.I cut new timber with my saw and inhaled the sweet sour smell of blackbutt. — 1985 formsblackbutts