An ansible is a category of fictional devices or technology capable of near-instantaneous or faster-than-light communication. It can send and receive messages to and from a corresponding device over any distance or obstacle whatsoever with no delay, even between star systems. As a name for such a device, the word "ansible" first appeared in a 1966 novel by Ursula K. Le Guin. Since that time, the term has been broadly used in the works of numerous science fiction authors, across a variety of settings and continuities. A related term is ultrawave. Coinage by Ursula Le Guin Ursula K. Le Guin coined the word "ansible" in her 1966 novel Rocannon's World. The word was a contraction of "answerable", as the device would allow its users to receive answers to their messages in a reasonable amount of time, even over interstellar distances. The ansible was the basis for creating a specific kind of interstellar civilizationone where communications between far-flung stars are instantaneous, but humans can only travel at relativistic speeds. Under these conditions, a full-fledged galactic empire is not possible, but there is a looser interstellar organization, in which several of Le Guin's protagonists are involved. Although Le Guin invented the name "ansible" for this type of device, fleshed out with specific details in her fictional works, the broader concept of instantaneous or faster-than-light communication had previously existed in science fiction. For example, similar communication functions were included in a device called an interocitor in the 1952 novel This Island Earth by Raymond F. Jones, and the 1955 film based on that novel, and in the "Dirac Communicator", which first appeared in James Blish's short story "Beep" (1954), which was later expanded into the novel The Quincunx of Time (1973). Robert A. Heinlein in Time for the Stars (1958) employed instantaneous telepathic communication between identical twin pairs over interstellar distances, and like Le Guin, provided a technical explanation based on a non-Einsteinian principle of simultaneity. In Le Guin's works In her subsequent works, Le Guin continued to develop the concept of the ansible: In The Left Hand of Darkness (1969), Le Guin writes that the ansible "doesn't involve radio waves, or any form of energy. The principle it works on, the constant of simultaneity, is analogous in some ways to gravity ... One point has to be fixed, on a planet of certain mass, but the other end is portable." In The