#1 shudder v. [shiver] shake, as from cold; "The children are shivering--turn on the heat!". wn
#2 shudder v. [shiver, throb, thrill] tremble convulsively, as from fear or excitement. wn
#3 shudder n. [frisson, shiver, chill, quiver, thrill, tingle] an almost pleasurable sensation of fright; "a frisson of surprise shot through him". wn
#4 shudder n. [tremor] an involuntary vibration (as if from illness or fear). wn
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