Entry 1 sense Webster, 1913 Arboriculture · Ar·bor·i·cul·ture · IPA /ɑːɹˈbɔːɹ.ɪˌkʌl.t͡ʃɚ/ 01 n. The cultivation of trees and shrubs, chiefly for timber or for ornamental purposes. 1. The cultivation of trees and shrubs, chiefly for timber or for ornamental purposes.