it means something that is incredibly good which you have tasted
boy 1: bro how is that cookie?
boy 2: it's actually dank, try it.
it means that the girl/ boy has been passed around so much. basically they're a slag and do anything with anyone
girl1: omg did you here what katie did?
girl2: no what did she do?
girl1: she fucked all of 10block
girl2: no way she's a badderz
8👍 4👎