Green’s Dictionary of Slang

1. (US campus) to do well or be something admirable, good.

1988		Eble Campus Sl. Oct. 8: rule – be beautiful, great: ‘She rules.’ ‘Man, this record rules.’.
1994		Eble Campus Sl. Apr.
2004		Eble Campus Sl. Apr.
2012		J. Fagan Panopticon (2013) 98: My cash is on Green, he’s a fat one. Fat babies rule.

2. (US black) to be in control.

1992		D. Burke Street Talk 2 50: Why do you always argue with your boss? He’s rulin’, not you!
2005		Mad mag. Oct. 24: They suck. We rule and we’re gonna kick their asses.