Green’s Dictionary of Slang

ham adj.2

[abbr.; hard as a motherfucker]

(US) tough, reckless, intense.

[US]C. Eble UNC-CH Campus Sl. Spring 2014 7: HAM — <hard as a mother fucker bold, reckless, intense: ‘Marcus Paige is going ham.’ ‘I totally went ham on yesterday’s exam’.