Obstreperous
WordNet
adjective
(1) Boisterously and noisily aggressive
"Kept up an obstreperous clamor"
(2) Noisily and stubbornly defiant
"Obstreperous boys"
WiktionaryText
Etymology
First attested circa 17th century, from obstreperus "clamorous, noisy," from obstrepere, "to make a noise against, oppose noisily," from ob-, "against" + strepere, "to noise."