Green’s Dictionary of Slang

used as a derog. intensifier.

1973		in Sun. Times Mag. 30 Sept. 38: If it had been me I’d have kicked him down. I’d have kicked him rassklatt down.
1983		C. Knight We Shall Not Die 11: How dem so rass claat wicked? [Ibid.] 83: All di owner goin’ to do is cuss to raas claat say somebody t’ief out some of him gas.
2003		B. Rai Crew 229: ‘I an’ 1 nuh deal wid Babylon.’ He grinned. ‘Lell her guh raasclaat self, Sleepy.’.