The definition of rowdy is noisy and disorderly.(adjective)
A crowd at a football game that is shouting, jumping up and down and making a lot of noise and chaos is an example of a rowdy crowd.
See rowdy in Webster's New World College Dictionary
noun pl. rowdies
Origin: < ? row
See rowdy in American Heritage Dictionary 4
noun pl. row·dies
Origin: Probably from row3.
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