Synonyms for Shivering (same or very similar meaning)
WordNet sense 1 (a sensation of cold that often marks the start of an infection and the development of a fever):
chill
WordNet sense 2 (vibrating slightly and irregularly; as e.g. with fear or cold or like the leaves of an aspen in a breeze):
shaky, trembling
WordNet sense 3 (subject to change or variation):
unsteady
From the ODE community, based on WordNet
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