bustling bust·ling UK/ˈbʌs(ə)lɪŋ/ US/ˈbʌslɪŋ/ uncommon adjective 1. full of energetic and noisy activity “a bustling city” Similaractive WordNet 2.1 (Princeton University). Wiktionary (CC BY-SA). CMU Pronouncing Dictionary. WordNet 2.1 Copyright Princeton University. All rights reserved.