Medium

Recording medium, a physical material that holds information expressed in any of the existing recording formats
- Mass media, such as film, radio or the World Wide Web
- A means of artistic expression, such as "the medium of painting" or "the medium of dance"

Medium (spirituality), a person who claims to serve as an intermediary between the living and the dead
Medium of instruction, the language used to educate in
Average, the sum of all the members of the set divided by the number of items in the set

In science:

Medium (optics), material through which waves propagate
Processing medium, in industrial engineering, a material that plays a role in manufacturing processes
Transmission medium, in physics, any material substance which can propagate waves or energy
Growth medium, in biotechnology, an object in which microorganisms or cells in experience growth
Interplanetary medium, in astronomy, material which fills the solar system
Interstellar medium, in astronomy, the matter and energy content that exists between the stars within a galaxy
Excitable medium, a nonlinear dynamical system which has the capacity to propagate a wave
Solvent in chemistry

In fiction:

Medium (TV series), a 2005–2006 television series about a research medium for a district attorney's office
The Medium, an opera by Gian-Carlo Menotti

See also