1907, as a theoretical system to transmit moving images over telegraph or telephone wires; formed in English or borrowed from French télévision, from tele- + vision.
Television is not impossible in theory. In practice it would be very costly without being capable of serious application. But we do not want that. On that day when it will be possible to accelerate our methods of telephotography by at least ten times, which does not appear to be impossible in the future, we shall arrive at television with a hundred telegraph wires. Then the problem of sight at a distance will without doubt cease to be a chimera. ["Telegraphing Pictures" in "Windsor Magazine," 1907]
Other proposals for the name of a then-hypothetical technology for sending pictures over distance were telephote (1880) and televista (1904). The technology was developed in the 1920s and '30s. Nativized in German as Fernsehen. Shortened form TV is from 1948. Meaning "a television set" is from 1941. Meaning "television as a medium" is from 1927.
Television is the first truly democratic culture -- the first culture available to everyone and entirely governed by what the people want. The most terrifying thing is what people do want. [Clive Barnes, "New York Times," Dec. 30, 1969]