Definition from Wiktionary, the free dictionary
- (pathology) Of, relating to, or affected by spasm.
- (pathology) Of or relating to spastic paralysis.
- (slang, pejorative) Clumsy.
- (slang, pejorative) Hyperactive, excited, and acting in a random manner.
of or relating to spastic paralysis
hyperactive, excited, and random manner
spastic (plural spastics)
- A person affected by spastic paralysis or spastic cerebral palsy.
- (slang, offensive) A stupid, clumsy person.
person affected by spastic paralysis or spastic cerebral palsy
one who is hyperactive
Derived terms 
Usage notes 
The word is perceived as relatively inoffensive in the United States, but extremely offensive in the United Kingdom.
- spastic in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913
- “spastic” in Douglas Harper, Online Etymology Dictionary (2001).