在一篇关于德国巴伐利亚服装的文章中
On a recent night, the dance floor of Neuraum was a festival
of dirndl in its endless varieties. There was a black goth
dirndl cascading over tattooed calves. Next to it, a gaggle of
pink and baby blue ones worn with sneakers. Young men sweating
in woolly calf warmers and felt hats were grinding up to young
women in flowery aprons.
倒数第二行中，grinding up 在文中的意思，要怎么理解比较好呢？
另外
Plus, for many, he said, "wearing a traditional outfit is a license
to get completely hammered whilst still feeling virtuous."
第二行中的 hammered 是什么意思呢？
谢谢!
原文
https://goo.gl/aH6mZX