Green’s Dictionary of Slang

spaz adj.

also spasmoid, spazz, spazz-out
[spaz n.]

uncoordinated.

[US]G. Tate ‘Atomic Dog’ in Flyboy in the Buttermilk (1992) 30: Funkadelic was too wacky for the souled-out splibs and too black for the spazz whiteys.
[US]S. King It (1987) 356: Richie, who had barely escaped what might have been a really bad beating at the hands of Henry and his spasmoid friends.
[US]D. Woodrell Muscle for the Wing 162: Skelton’s spaz reactions to the living dead [...] caused Shuggie to roar.
[US]B. Hamper Rivethead (1992) 82: I loaded up on spazz-out masterpieces by the likes of Arthur Conley; the Troggs [...] and the Bobby Fuller Four.