Surpassing other examples of its kind; extraordinary.
(prefix): In precise scientific language "one million"
(idiom): To be extremely or excessively enthusiastic about.
mega nuts (comp. adj):
Very, very crazy.
A freak occurrence or scenario that is mega in size and extraordinarily nuts.
(idiom): Inexplicably enthusiastic about something.
Person A: "Did you see Dave's new hair last night? Weird. And he was going on about burning all his worldly possessions and starting a commune."
Person B: "Mega nuts."