spastic, adj. — Green’s Dictionary of Slang

spastic adj.

[SE spastic, afflicted by spastic paralysis, characterized by sudden muscle spasm; these senses are generally considered unacceptable since they are, in effect, a derog. attack on those who suffer this paralysis]

1. uncoordinated, socially unacceptable.

1961		H. Ellison Rockabilly (1963) 92: Stag a taffy-limbed, spastic bundle of dirty clothes unable to stand or speak.
1977		Sun. Times Rev. 21 Aug. 29: The city fathers forbade rock and roll [...] because it ‘attracted undesirable elements given to practising their spastic gyrations’.
1983		G. Tate ‘King Sunny Adé’ in Flyboy in the Buttermilk (1992) 61: An African brother [...] gets to swaying in front of this punk and slows his slam down to a spastic grind.
1997		W.W. Johnstone Alone in the Ashes 303: Leroy, you spastic bastard!
2005		H. Mantel Beyond Black 132: They’d been calling me spastic all afternoon.

2. dull, foolish.

1960		G. Swarthout Where the Boys Are 7: The most spastic thing about East Swander is that you have to maturate simultaneously with a thousand other girls.
1975		G. Underwood ‘Razorback Sl.’ in AS L:1/2 67: spastic 1: adj [...] Dull, foolish, stupid.
2008		J. Niven Kill Your Friends (2009) 12: ‘Eclectic,’ as spastic musicians say when they’re trying to sound clever in interviews.

In derivatives

spastically (adv.)

(US) helplessly.

1960

G. Swarthout Where the Boys Are 48: I was already in love with him; desperately and spastically in love with him.

spasticated (adj.)

a general term of derision, implying physical inadequacy.

1998		I. Welsh Filth 326: What is that spasticated cow wanting from me?
2001		OnLine Dict. of Playground Sl. 🌐 spack, spaz, spazmo, spacker, spanner, spadge n. [...] An excessively stupid or unpleasant person. (also adj. spasticated, spazzy, spazzed).
2003		Ouch! 24 Jan. 🌐 Oi, Hookie ... Hookie wookie! Evil one-eyed hook monster freak! Spasticated religious cripple monster villain gimp! Um, that’ll do for now I think.