Synonyms for Spastic (same or very similar meaning)
WordNet sense 1 (affected by an impairment of normal physical or mental function):
ill, sick
WordNet sense 2 (affected by involuntary jerky muscular contractions; resembling a spasm):
convulsive, spasmodic
WordNet sense 3 (subject to change or variation):
unsteady
From the ODE community, based on WordNet
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