Tremor

n. trembling, shudder, shock, shaking, vibration

For the film see Tremors (film). For other uses, see Tremor (disambiguation). Tremor is an unintentional, somewhat rhythmic, muscle movement involving to-and-fro movements (oscillations) of one or more parts of the body. It is the most common of all involuntary movements and can affect the hands, arms, head, face, vocal cords, trunk, and legs. Most tremors occur in the hands. In some people, tremor is a symptom of another neurological disorder. The most common form of tremor, however, occurs in otherwise healthy people. Although tremor is not life-threatening, it can be embarrassing to some people and make it harder to perform daily tasks.
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Tremor /trem·or/ an involuntary trembling or quivering. action tremor rhythmic, oscillatory, involuntary movements of the outstretched upper limb; [more]Tremor - Community and Resources

Noun
1. an involuntary vibration (as if from illness or fear)
(synonym) shudder
(hypernym) vibration, quiver, quivering
2. a small earthquake
(synonym) earth tremor, microseism
(hypernym) earthquake, quake, temblor, seism
(hyponym) aftershock
(derivation) quake
3. shaking or trembling (usually resulting from weakness or stress or disease)
(hypernym) shaking, shakiness, trembling, quiver, quivering, vibration, palpitation
(hyponym) essential tremor
(part-holonym) paralysis agitans, Parkinsonism, Parkinson's disease, Parkinson's syndrome, Parkinson's, shaking palsy
Verb
1. shake with seismic vibrations; "The earth was quaking"
(synonym) quake
(hypernym) shake, agitate
(derivation) earth tremor, microseism

n. tremor, trembling