When waves are used to describe girls, they mean two things:
1.
Let Baidu swing; Indulge [unrestrained; Debauchery]
Laugh at the waves. -"Poetry, Strong Wind and Final Wind"
2. Another example is: Bo disciple (called fanatic, I don't know how to stop); Wave Baidu things (bad things; Annoying); Wandering in Baidu (a disparaging term for people who don't check Baidu)
Nizi means girl, which is more dramatic (close but not solemn)