look up any word, like cleveland steamer:
A) A male who has contracted venereal disease from sleeping with the 'nastybox' of a nastybix

B) A male version of nastybix. To be avoided at all costs by both males and females.

Identifying features:
Painful walk
Painful smile
Painful frown
"Stay away from him. I heard he's been with Bianca and now he's a Nastydax"

"I got me some Daks. NASTYdax! Mwahahah "

"My Nastydax are serious man. Clearasil don't help!"

by t. thyme-cookie November 30, 2006