bois·ter·ous 
(boistər-əs, -strəs)
(boistər-əs, -strəs)adj.
1. Loud or noisy and lively or unrestrained: a boisterous street market. See Synonyms at vociferous.
2. Rough and stormy; violent: boisterous winds; a boisterous voyage.
[Middle English boistres, variant of boistous, rude, rough, perhaps from Old French boisteus, lame, limping, from boiste, knee joint.]
boister·ous·ly adv.
boister·ous·ness n.