genus Haematoxylum ge·nus·hae·matoxylum uncommon noun 1. small genus of tropical American spiny bushy shrubs or trees SynonymsHaematoxylumgenus HaematoxylumHaematoxylongenus Haematoxylon Related words Broader terms rosid dicot genus Parts Caesalpinioideae Part of logwood WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.