from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A broadcast of an event or a recording of an event over the World Wide Web: a webcast of the solar eclipse.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A video and/or audio broadcast transmitted via the Internet
- v. To make such a broadcast
web + (broad)cast.(American Heritage® Dictionary of the English Language, Fourth Edition)
Blend of web and broadcast (Wiktionary)