waanzinnig

Etymology
Borrowed from. Equivalent to. Related is slightly more recent. For the informal positive meaning, adverbial use is more common than adjectival use.

Adjective

 * 1)  out of his/her mind, insane, mad
 * 2)  crazy, fantastic outrageous; extreme

Adverb

 * 1) in an insane way
 * 2)  incredibly, extremely (well or good)
 * 3) * 1980, Herman Pieter de Boer, "Ik heb zo waanzinnig gedroomd", Kinderen voor Kinderen, Kinderen voor Kinderen 1.
 * "nl"

- Ik heb zo wa-wa-wa-waanzinnig gedroomd