arboreal UK /ɑːˈbɔːɹɪ.əl/US /ɑɹˈbɔɹi.əl/adjective 3noun 1forms 3 adjective3 •Of, relating to, or resembling a tree.High and sacred, in good troth, is the power of the microcosmical spirit, which without any arboreal trunck produceth a true Cherry: — 1650 •Living in or among trees.If the harvest mouse had been more strictly arboreal, it would perhaps have had its tail rendered structurally prehensile, as is the case with some members of the same order. — 1872 •Covered or filled with trees.The breadth of the arboreal landscape requires a longer list of living creatures, and creatures of greater bulk. — 1885 noun1 •Any tree-dwelling creature.So, by learning to use their eyes to more and more advantage the arboreals added another treasure to the foundation of human intelligence. — 1971 formsarboreals · more arboreal · most arboreal