broadcast

Where it comes from

Broadcast ordinarily means a programme or message transmitted by radio, television, or another mass medium. Broadcast began as an agricultural expression built from broad and cast, throw. To sow seed broadcast was to scatter it widely over the ground, especially by hand, rather than place it in individual rows or holes. The word gained a figurative sense of spreading something widely before radio.

How the meaning developed

In the early 1920s, that established image was applied to transmissions sent from one source to a dispersed audience, and radio made the media sense dominant.