Clairvoyance is a word borrowed from the French. Clairvoyance means "clear vision" or "clear-sighted".
It generally it describes the ability to perceive the events and receiving information, without the use of the known senses. Information can be seen at great distances, and across time. Clairvoyance is divided into several different categories.
Clairvoyance is best known, where a clairvoyant tells about the deceased. Clairvoyants are often asked for advice in relation to haunting of houses.
So-called "clairvoyant-meetings" are different from seances. Clairvoyance deal with information, essentially only in one direction. This means you do not have opportunity to ask questions "back".
A kind of clairvoyance - also known as Remote Viewing, has been extensively used. During the cold war, both superpowers security services invested huge sums in Remote Viewing. Here was a person for example told to "see" what was happening on a specific coordinate.
The results were so convincing that the experiments in the United States stopped as late as 1995 with a budget of $ 20 million. The project was called "Stargate".