Latin 'vociferari' — literally 'to carry one's voice,' same pattern as 'Lucifer' (light-carrier).
Vehement or clamorous in expressing one's views; loud and forceful.
From Latin 'vōciferārī' (to cry out loudly, to shout, to clamour), itself composed of 'vōx' (voice, genitive 'vōcis') + 'ferre' (to carry, to bear, to bring). The compound literally means 'to carry one's voice' — to project it outward with force and persistence. 'Ferre' comes from PIE *bʰer- (to carry, to bear), one of the most ancient and widely distributed PIE roots
The compound 'vōx + ferre' (voice + carry) follows the same pattern as 'Lucifer' (lux + ferre, light-carrier), 'conifer' (conus + ferre, cone-bearer), and 'crucifer' (crux + ferre, cross-bearer). Latin loved these '-fer' compounds: they describe someone or something that carries a specified thing. A vociferous person is literally a voice-carrier — someone who