侮辱人的说法，认为某人来自社会底层，其性格、行为、衣着没有教养。an insulting way to describe a person, or their behaviour, clothes, etc. that is thought to show a lack of education and low social class
Personally, I find personalized number plates a bit chavvy. 我个人觉得挂个性化车牌是挺俗气的。
a chavvy schoolgirl 一个没教养的女学生
See: chav