The word 'webcast' is a modern portmanteau, a blend of two distinct English words. The first element, 'web,' is a metaphorical extension from its Old English root meaning a woven cloth, now universally referring to the interconnected network of the World Wide Web. The second element, 'cast,' derives from Old Norse via Middle English, originally meaning to throw, which evolved semantically to mean to throw one's voice or image, as in 'broadcast.' The compound 'webcast' was formed in the late 20th century by analogy with 'broadcast,' precisely describing the act of transmitting audio-visual content specifically via the internet rather than traditional radio or television waves. Its formation follows a clear and logical pattern in English where 'web-' specifies the medium, and '-cast' specifies the action.

Structure: web (network) + cast (transmit) - web: Origin: Old English webb (woven fabric). Role: A combining form meaning "of or relating to the World Wide Web." - cast: Origin: Old Norse kasta (to throw). Role: A combining form meaning "to transmit or broadcast."