Tremble means to shake involuntarily, often out of fear or because you are cold.(verb)
The definition of tremble is a quiver or shake, often that occurs because of fear or cold.(noun)
When your voice is quivering, this is an example of a situation where there is a tremble in your voice.
See tremble in Webster's New World College Dictionary
Origin: ME tremblen < OFr trembler < VL *tremulare < L tremulus, trembling < tremere, to tremble < IE *trem- (< base *ter-) > Gr tremein, to tremble
See tremble in American Heritage Dictionary 4
intransitive verb trem·bled, trem·bling, trem·bles
Origin: Middle English tremblen
Origin: , from Old French trembler
Origin: , from Vulgar Latin *tremulāre
Origin: , from Latin tremulus, trembling; see tremulous.
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