Synonym: quavering. Similar words: tremulously, fabulous, credulous, querulous, nebulous, incredulous, garrulous, ridiculous. Meaning: ['tremjələs /-jʊl-] 
adj. (of the voice) quivering as from weakness or fear.
adj. (of the voice) quivering as from weakness or fear. 31. Their optimism is apt to be decidedly conditional and tremulous.
More similar words: tremulously, fabulous, credulous, querulous, nebulous, incredulous, garrulous, ridiculous, meticulous, scrupulous, fantabulous, incredulously, tremendous, emulate, tremor, extreme, trembling, extremely, extremity, blouse, tumultuous, perilous, jealous, libelous, frivolous, simultaneously, strenuous, anomalously, obstreperous, bemused.