shudder
noun.
an almost pleasurable sensation of fright
a frisson of surprise shot through him
noun.
an involuntary vibration (as if from illness or fear)
Synonym: tremor
verb.
shake, as from cold
The children are shivering--turn on the heat!
Synonym: shiver
verb.
tremble convulsively, as from fear or excitement
Synonym: shiver, thrill, throb